Combined Navigation Comprehensive Calibration Method, Device and Equipment Based on Intelligent Damping Switching

Abstract

To improve the navigation accuracy of a submersible vehicle during its long-range global navigation, the present invention proposes a combined navigation comprehensive correction method, device, and equipment based on intelligent damping switching. During the navigation of the submersible vehicle, the navigation positioning result of the current fault-tolerant damping is output based on the damping algorithm; when satellite signals can be acquired, different correction methods are selected to correct the navigation positioning result of the current fault-tolerant damping, and the corrected navigation positioning result is output. The switching of the damping algorithm improves the short-term accuracy of navigation, and the comprehensive correction algorithm improves the long-term accuracy of navigation. By combining the advantages of damping switching and intelligent comprehensive correction, damping switching and comprehensive correction are performed according to the complex sea conditions and the number of times the submersible vehicle surfaces, thereby improving the short-term and long-term accuracy of navigation positioning.

Description

Technical Field

[0001] The present invention belongs to the technical field of combined navigation, and in particular to a combined navigation comprehensive correction method, device and equipment based on intelligent damping switching. Background Art

[0002] In the context of deep-sea global navigation, the damping algorithm is the primary algorithm for combined inertial and Doppler velocity (DVL) navigation. When Doppler velocity measurement accuracy deteriorates, the damping algorithm must be switched. While the damping switching algorithm improves short-term navigation accuracy, long-term accuracy requires a comprehensive correction algorithm. To maintain the submersible's stealth, it may only surface once a day or even several days to acquire satellite signals during actual missions.

[0003] Currently, there are two types of comprehensive correction algorithms: two-point correction and three-point correction. Traditional comprehensive correction algorithms only study the application of one of them in integrated navigation, and do not fully consider the factor that the number of times satellite signals can be obtained in the entire mission cannot be determined. Therefore, the accuracy of the current comprehensive correction algorithm is limited. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a combined navigation comprehensive correction method, device and equipment based on intelligent damping switching.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] In one aspect, the present invention provides a combined navigation comprehensive correction method based on intelligent damping switching, comprising:

[0007] During the navigation process of the submersible, the current fault-tolerant damping navigation positioning result is output based on the damping algorithm;

[0008] When satellite signals can be acquired, different correction methods are selected to correct the current fault-tolerant and damped navigation and positioning results, and the corrected navigation and positioning results are output, including:

[0009] When the satellite reference point is first acquired, only the position is reset. The navigation positioning result currently output is the fault-tolerant and damped navigation positioning result after the position reset.

[0010] For the next acquired satellite reference point, first determine whether the current satellite reference point is a valid point according to the failure point criterion. If the current satellite reference point is a failure point, perform position reset. The currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect. If the currently acquired satellite reference point is a valid point, the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect. If two consecutive currently acquired satellite reference points are valid points, further estimate and compensate for the equivalent azimuth gyro drift on the premise of position reset, perform two-point calibration to correct the currently fault-tolerant damping navigation and positioning result, and output the navigation and positioning result after two-point calibration, improving the long-term positioning accuracy. If three consecutive currently acquired satellite reference points are valid points, further estimate and compensate for the equivalent azimuth gyro drift and horizontal gyro drift on the premise of position reset, perform three-point calibration to correct the currently fault-tolerant damping navigation and positioning result, and output the navigation and positioning result after three-point calibration, improving the long-term positioning accuracy.

[0011] Further, judge the satellite reference point according to the failure point criterion. The method is as follows:

[0012] Calculate the matrix corresponding to the current satellite reference point based on the satellite observation matrix and the state transition matrix :

[0013]

[0014] Where represents the state transition matrix from the time when the previous satellite reference point was acquired to the time when the current satellite reference point was acquired , respectively represent time, the satellite observation matrix at time;

[0015] Calculate the condition number of the matrix corresponding to the current satellite reference point ;

[0016] Judge whether the current satellite reference point is a failure point according to the condition number of the matrix corresponding to the current satellite reference point.

[0017] Further, when the condition number of the matrix corresponding to the current satellite reference point is greater than the set threshold, it is considered that the condition number is too large, and the matrix corresponding to the current satellite reference point is prone to singularity, the gyro drift result is abnormal, and the current satellite reference point is a failure point. Otherwise, the current satellite reference point is a valid point.

[0018] Furthermore, during the navigation of the submersible, the measurement residual of the current Doppler tester is obtained in real time and input into a pre-trained damping switching threshold prediction model based on an artificial neural network, and the damping switching threshold is predicted online in real time to realize damping switching.

[0019] Furthermore, a training method for a damping switching threshold prediction model based on an artificial neural network includes:

[0020] Add different classical noises to the Doppler tester, including but not limited to step noise, periodic oscillation noise, ramp noise, and ramp sinusoidal noise, and perform chi-square test on the navigation data of the Doppler tester after adding the different classical noises;

[0021] The K-means method is used to classify the chi-square detection results of the Doppler tester navigation data after adding different classical noises, and the cluster centers under different classical noises are obtained as the expected chi-square detection thresholds under the corresponding classical noises.

[0022] The measurement residuals of the Doppler tester corresponding to the navigation data of the Doppler tester after adding different classical noises are used as input data, and the expected chi-square detection thresholds under different classical noises are used as labels. The constructed artificial neural network is trained to obtain a trained damping switching threshold prediction model based on the artificial neural network.

[0023] On the other hand, a combined navigation comprehensive correction device based on intelligent damping switching is provided, comprising:

[0024] The first module is used to output the current fault-tolerant damping navigation positioning result based on the damping algorithm during the navigation of the submersible;

[0025] The second module is used to select different correction methods to correct the current fault-tolerant and damped navigation positioning results when satellite signals can be acquired, and output the corrected navigation positioning results, including:

[0026] When the satellite reference point is first acquired, only the position is reset, and the navigation positioning result currently output is the current fault-tolerant and damped navigation positioning result;

[0027] For the next acquired satellite reference point, first determine whether the current satellite reference point is a valid point according to the failure point criterion. If the current satellite reference point is a failure point, perform position reset. The currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect. If the currently acquired satellite reference point is a valid point, the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect. If two consecutive satellite reference points are acquired as valid points currently, further estimate and compensate the equivalent azimuth gyro drift on the premise of position reset, perform two-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after two-point calibration, improving the long-term positioning accuracy. If three consecutive satellite reference points are acquired as valid points currently, further estimate and compensate the equivalent azimuth gyro drift and horizontal gyro drift on the premise of position reset, perform three-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after three-point calibration, improving the long-term positioning accuracy.

[0028] On the other hand, the present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the above-mentioned combined navigation comprehensive correction method based on intelligent damping switching are implemented.

[0029] On the other hand, the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned combined navigation comprehensive correction method based on intelligent damping switching are implemented.

[0030] On the other hand, the present invention provides a computer program product. The computer program product is stored on a computer-readable storage medium and includes computer instructions. When the computer instructions are run by a processor, the computer device is enabled to implement the steps of the above-mentioned combined navigation comprehensive correction method based on intelligent damping switching.

[0031] Compared with the prior art, the technical effects of the present invention are as follows:

[0032] To maintain the stealth of the submersible, in actual missions, it may surface to obtain satellite signals only once a day or even several days. The comprehensive correction algorithm has two-point calibration and three-point calibration. The traditional comprehensive correction algorithm only studies the application of one of them in integrated navigation and does not utilize satellite signals for calibration with maximum efficiency. The present invention proposes a comprehensive correction algorithm for typical mission scenarios and decides whether to perform position reset according to the failure point criterion. The present invention improves the utilization rate of satellite reference points and the long-term accuracy of navigation and positioning.

[0033] The inertial navigation damping algorithm is the prerequisite for comprehensive correction. It is divided into undamped, internally damped, and externally damped states. Switching the damping algorithm improves short-term navigation accuracy, while the comprehensive correction algorithm improves long-term navigation accuracy. Facing the complex sea conditions of the deep sea, this system combines the advantages of damping switching and intelligent comprehensive correction. Damping switching and comprehensive correction are performed based on complex sea conditions and the number of times the submersible surfaced, improving both short-term and long-term navigation positioning accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0035] Figure 1 Flowchart of a combined navigation comprehensive correction method based on intelligent damping switching provided in one embodiment;

[0036] Figure 2 A schematic diagram of selecting different correction methods according to the conditions of the acquired satellite reference points in one embodiment;

[0037] Figure 3 A schematic diagram of the navigation trajectory of a submersible in one embodiment;

[0038] Figure 4 This is a comparison chart of positioning errors of the three navigation and positioning methods in Experiment 1;

[0039] Figure 5 This is a comparison chart of positioning errors of the three navigation positioning methods in Experiment 2;

[0040] Figure 6 This is a comparison chart of the positioning errors of the three navigation and positioning methods in Experiment 3. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0042] Reference Figure 1 In one embodiment, a combined navigation comprehensive correction method based on intelligent damping switching is provided, comprising:

[0043] During the navigation of the submersible, the navigation and positioning result of the current fault-tolerant damping is output based on the damping algorithm;

[0044] When satellite signals can be acquired, different calibration methods are selected to calibrate the navigation and positioning result of the current fault-tolerant damping, and the calibrated navigation and positioning result is output.

[0045] The Doppler velocity log (DVL) is the basis for the inertial Doppler integrated navigation of the submersible. When a speed measurement fault occurs in the Doppler velocity log, damping needs to be switched. When no fault occurs in the Doppler velocity log, the measurement residual follows a zero-mean Gaussian white noise distribution, and its mean and covariance can be estimated by mathematical statistics methods. At the same time, the navigation system can measure and record the measurement residual. When a speed measurement fault occurs in the Doppler velocity log, the mean and covariance of the measurement error deviate from those obtained by measurement. Therefore, it is usually determined whether to switch the damping based on the mean and covariance of the measurement error.

[0046] When the submersible is navigating normally, the Doppler velocity log has high speed measurement accuracy, and the external damping algorithm is usually adopted; when the submarine makes a maneuvering turn, there is a lateral drift velocity of the submarine hull, and there is a lateral velocity error in the speed measurement of the Doppler velocity log, which affects the navigation solution accuracy of the external damping algorithm, and the damping algorithm needs to be switched; when the submarine encounters strong fluctuations in ocean currents during navigation, the instantaneous speed measurement error of the Doppler velocity log will be relatively large, and the damping algorithm also needs to be switched; when the submarine makes up and down movements, affected by the salinity, temperature and water depth of the sea water, the change in the speed of sound changes, and the damping algorithm also needs to be switched. In addition, the Doppler velocity log belongs to an active sonar, and it is easy to be detected by anti-submarine sonars when it is working.

[0047] When there is no anti-submarine sonar in the navigation area of the submarine, the Doppler velocity log can be turned on and work normally. The damping algorithm of INS / DVL integrated navigation is adopted. When the speed measurement accuracy of the Doppler velocity log is high, the external damping algorithm is adopted; when the speed measurement accuracy of the Doppler velocity log is low, it is judged according to the maneuvering state of the submarine. When the submarine has a small maneuver (approximate uniform linear motion), the internal damping is the best algorithm. When the submarine has a large maneuver, the pure inertial navigation solution without damping is the best algorithm. When the submarine passes through the anti-submarine sonar array area, in order to maintain the concealment of the submarine, the Doppler velocity log needs to be turned off, and the damping algorithm is selected according to the maneuvering state of the submarine. When the submarine has a small maneuver (such as approximate uniform linear motion), the internal damping is the best algorithm. When the submarine has a large maneuver, the pure inertial navigation solution without damping is the best algorithm.

[0048] The K-means method is a classic clustering algorithm that can divide data into multiple clusters, and the data within each cluster is as similar as possible. In the present invention, the K-means method is used to classify the measurement residuals in various classic noise situations into two categories, namely, the Doppler tester has normal speed measurement and abnormal speed measurement of the Doppler tester. The clustering center of the abnormal category is regarded as the threshold for damping switching in this noise situation. When the recorded measurement residual reaches this threshold, damping switching can be performed.

[0049] In another embodiment, during the navigation of the submersible, the current measurement residual of the Doppler tester is obtained in real time and input into a pre-trained damping switching threshold prediction model based on an artificial neural network to predict the damping switching threshold online in real time and achieve damping switching. Among them, the training method of the damping switching threshold prediction model based on an artificial neural network includes:

[0050] Different classic noises are added to the Doppler tester, including but not limited to step noise, periodic oscillation noise, ramp noise, and ramp sine noise, and chi-square detection is performed on the navigation data of the Doppler tester after adding different classic noises;

[0051] The K-means method is used to classify the chi-square detection results of the navigation data of the Doppler tester after adding different classic noises, and the clustering centers under different classic noises are obtained as the expected chi-square detection thresholds under the corresponding classic noises;

[0052] The measurement residuals of the Doppler tester corresponding to the navigation data of the Doppler tester after adding different classic noises are used as input data, and the expected chi-square detection thresholds under different classic noises are used as labels to train the constructed artificial neural network to obtain a trained damping switching threshold prediction model based on an artificial neural network.

[0053] The traditional comprehensive calibration algorithm needs to be carried out under the navigation conditions of equal latitude and low speed, and its practicability is greatly limited. The comprehensive calibration algorithm adopted in the present invention includes two-point calibration and three-point calibration. The rotation modulation inertial navigation can suppress the gyro drift in the horizontal direction. The main error influencing factor is the residual equivalent azimuth gyro drift. The two-point calibration method can estimate the equivalent azimuth gyro drift, but cannot estimate the gyro drift in the horizontal direction. The three-point calibration method can estimate the gyro drift in the horizontal direction, and then compensate the gyro constant drift of the system. When there is a satellite signal, matrix operation will be performed during calibration. When the condition number of the matrix is too large, the matrix operation is prone to singularity, and the calculated gyro drift result appears abnormally. Such a calibration point is called a failure point. The comprehensive calibration needs to avoid the failure point. When encountering a failure point, the gyro drift is not calculated, and only the position reset is performed. According to the order of obtaining the satellite reference points, if the first point is a failure point, the position reset is performed. If two consecutive valid points appear, the two-point calibration is performed. If three consecutive valid points appear, the three-point calibration is performed. The position reset can replace the inertial navigation positioning result with the satellite reference point, and the positioning error instantly becomes zero, improving the short-term positioning accuracy by means of external information. On the premise of position reset, the comprehensive calibration further estimates the gyro drift error, substitutes the gyro drift error into the inertial navigation error model to calculate the positioning error caused by the gyro drift error, and compensates the positioning error at the output end of the inertial navigation positioning, reducing the positioning error caused by the internal factor of gyro drift and improving the long-term positioning accuracy.

[0054] The two-point calibration and three-point calibration described in the present invention can be implemented by using the two-point calibration and three-point calibration methods commonly used in the technical solutions in the prior art in this field. Preferably, the two-point calibration method adopted is the two-point calibration method based on the normal vector position model, and the three-point calibration method adopted is the three-point calibration method based on the normal vector position model. The two-point calibration method based on the normal vector position model does not require the course reference information and does not need to navigate under the conditions of equal latitude and small maneuvering state, improving the applicability of the submersible navigation in complex environments. The two-point calibration method based on the normal vector position model can estimate the equivalent azimuth gyro drift, but cannot estimate the gyro drift in the horizontal direction. The three-point calibration method based on the normal vector position model can not only estimate the equivalent azimuth gyro drift, but also estimate the gyro drift in the horizontal direction, and then compensate the gyro constant drift of the system and correct the position error.

[0055] Specifically, when the satellite signal can be obtained, different calibration methods are selected according to the order of the obtained satellite reference points and the validity of the satellite reference points to calibrate the navigation and positioning results of the current fault tolerance damping, including:

[0056] When the satellite reference point is obtained for the first time, the position reset is performed, and the current output navigation and positioning result is the navigation and positioning result of the fault tolerance damping after the position reset;

[0057] For the next obtained satellite reference point, first determine whether the current satellite reference point is a valid point according to the failure point criterion. If the current satellite reference point is a failure point, perform position reset. The currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect; if the currently obtained satellite reference point is a valid point, the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect; if two consecutive currently obtained satellite reference points are valid points, further estimate and compensate for the equivalent azimuth gyro drift on the premise of position reset, perform two-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after two-point calibration, improving the long-term positioning accuracy; if three consecutive currently obtained satellite reference points are valid points, further estimate and compensate for the equivalent azimuth gyro drift and horizontal gyro drift on the premise of position reset, perform three-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after three-point calibration, improving the long-term positioning accuracy.

[0058] Refer to Figure 2 , in an embodiment of the present invention, the method for judging the satellite reference point according to the failure point criterion is as follows:

[0059] Calculate the matrix corresponding to the current satellite reference point based on the satellite observation matrix and the state transition matrix :

[0060] ;

[0061] Where represents the state transition matrix from the time when the previous satellite reference point was obtained to the time when the current satellite reference point was obtained , respectively represent time, time satellite observation matrix;

[0062] Calculate the condition number of the matrix corresponding to the current satellite reference point ;

[0063] Judge whether the current satellite reference point is a failure point according to the condition number of the matrix corresponding to the current satellite reference point. When the condition number of the matrix corresponding to the current satellite reference point is greater than the set threshold, it is considered that the condition number is too large, and the matrix corresponding to the current satellite reference point is prone to singularity, and the gyro drift result is abnormal. The current satellite reference point is a failure point, otherwise the current satellite reference point is a valid point.

[0064] ;

[0065] Wherein:

[0066] ;

[0067] is the angular velocity of the Earth's rotation, is the time difference between two observations. From the time of obtaining the satellite reference point in the previous time to the time of obtaining the satellite reference point currently, during this period, for each it corresponds to the time difference from the -1 moment to the k -1 moment to the k moment, k The value range of .

[0068] ;

[0069] ;

[0070] ;

[0071] Wherein is the unit vector from the center of the virtual sphere to the position of the carrier, including x , y , z components in three directions , wherein is the latitude, is the longitude, is the transverse latitude, is the transverse longitude.

[0072] ;

[0073] Wherein is the time constant related to the Markov process.

[0074] Regarding the set threshold corresponding to the condition number , those skilled in the art can set it according to the actual situation and experience. Without loss of generality, the normal value range of the condition number can be obtained from historical data, and the mean value of the normal value range of the condition number is obtained. When the condition number is greater than 100 times the mean value of the normal value, it is considered that the condition number is too large, matrix operations are prone to singularity, and the calculated gyro drift result is abnormal. This calibration point is a failure point; comprehensive calibration should avoid the failure point, and only perform position reset instead of gyro drift calculation when encountering the failure point.

[0075] The damping algorithm switching improves the short-term accuracy of navigation, and the comprehensive correction algorithm improves the long-term accuracy of navigation. Traditional methods study the two separately. In the face of the complex sea conditions in the deep and far seas, the present invention combines the advantages of the two and proposes a comprehensive correction method based on intelligent damping switching, which intelligently performs damping switching and comprehensive correction according to the typical task scenarios of complex sea conditions and the number of times the submersible floats, improving the navigation accuracy and the adaptability of the algorithm.

[0076] To verify the damping switching and comprehensive correction algorithms, the trajectories of typical task scenarios are adopted. During the navigation process, the submersible successively experiences three typical task scenarios: large maneuvers of the submersible, violent fluctuations of ocean currents, and encountering anti-submarine sonar, and the switching of the fault-tolerant damping algorithm is required; in addition, the submersible floats to the water surface three times at 35h, 55h, and 80h to receive satellite signals, and the satellite signals can be used for comprehensive correction.

[0077] Refer to Figure 3 , which is a schematic diagram of the submersible navigation trajectory. The submersible starts to navigate from a depth of -300m at 90° east longitude and 45° north latitude, with a course angle of 45° east of north. It remains stationary for 6h for initial alignment, accelerates uniformly to 5m / s in 20s, and then sails in a straight line at a constant speed of 5m / s; it starts to float at 30h, reaches the water surface after 310s to receive satellite signals for 80s, then dives to a depth of -300m after 310s and continues to sail in a straight line at a constant speed of 5m / s; it starts to maneuver at 40h, turns right at 0.5° / s for 180s, continues to sail at a constant speed for 1h, turns left at 0.5° / s for 360s, sails at a constant speed for 2h, turns right at 0.5° / s for 360s, sails at a constant speed for 1h, turns left at 0.5° / s for 180s, and sails at a constant speed until 70h; it starts to float at 70h, reaches the water surface after 310s to receive satellite signals for 80s, then dives to a depth of -300m after 310s and continues to sail in a straight line at a constant speed of 5m / s until 80h; at 80h, the DVL is turned off, and it floats up to a depth of -40m at a constant speed in 270s, keeps the depth unchanged, continues to sail forward at a constant speed of 5m / s for 12h, turns right at 1° / s for 90s, sails forward at a constant speed for 900s, turns left at 1° / s for 90s; it dives to a depth of -300 at 278s and continues to sail forward at a constant speed of 5m / s until 100h; it starts to float at 100h, reaches the water surface after 310s to receive satellite signals for 80s, then dives to a depth of -300m after 310s and continues to sail in a straight line at a constant speed of 5m / s until it reaches the end point at 140h.

[0078] (I) Simulation steps

[0079] To validate the damping switching algorithm, known common noise was added to the Doppler tester. The navigation data was then processed to generate a chi-squared test function, which was found to correspond to the fault time. After adding various classic noises to the Doppler tester, a chi-squared test was performed for each case. K-means was then used for classification, with the largest cluster center being used as the expected threshold for that case.

[0080] The Doppler tester measurement residuals in each case were used as input data, the corresponding thresholds determined using the K-means method were used as labels, and the number of hidden layers was set to 8. The network was trained on the data obtained above. A set of data was then extracted for prediction verification.

[0081] In order to achieve the purpose of real-time prediction of the damping switching threshold, the trained neural network is finally embedded in the integrated navigation program to realize online judgment of the threshold and damping switching. The offline judgment threshold and the online judgment threshold are compared with the expected threshold to observe their stability and accuracy in online use.

[0082] Table 1 compares threshold determination using artificial neural networks. Neural networks achieve good results for both offline and online threshold determination, with acceptable errors, essentially achieving the intended purpose. Discrepancies between offline and online threshold determinations are attributed to insufficient training data, which can lead to variations in each neural network build. Verification has shown that with more training data, the neural network becomes more stable, the differences in threshold determination decrease, and the prediction results improve.

[0083] Table 1 Comparison of artificial neural network threshold judgment

[0084]

[0085] Next, the submersible surfaced three times at 35h, 55h and 80h to receive satellite signals, and all of them were judged to be valid points.

[0086] Reference Figure 4 , Figure 4 This is a comparison chart of the positioning errors of the three navigation positioning methods in Experiment 1. Figure 4 Here, “pure inertial navigation” refers to navigation and positioning based on pure inertial navigation, “traditional method” refers to navigation and positioning using traditional damping switching algorithm, and “the method in this paper” refers to positioning based on damping switching combined with two-point correction. Figure 4It can be seen that the damping switching combined with the two-point correction positioning method is superior to the "pure inertial navigation" and the "traditional method". Using the damping switching combined with the two-point correction positioning method, two-point correction positioning is performed at 35h, 55h, and 80h during the submarine's navigation. The maximum positioning error from 55h to 80h is 2.46 n mile; after 80h, the maximum positioning error and RMS of the damping switching combined with the two-point correction positioning method are 3.78 n mile and 2.28 n mile, respectively.

[0087] Refer to Figure 5 , Figure 5 Figure is the comparison chart of the positioning errors of the three navigation and positioning methods in Experiment 2. Figure 5 In, "pure inertial navigation" represents navigation and positioning based on pure inertial navigation, "traditional method" represents navigation and positioning using the traditional damping switching algorithm, and "method of this paper" represents the damping switching combined with the three-point correction positioning. It can be seen from Figure 5 that the damping switching combined with the three-point correction positioning method is superior to the "pure inertial navigation" and the "traditional method". Using the damping switching combined with the three-point correction positioning, three-point correction positioning is performed at 35h, 55h, and 80h during the submarine's navigation. The maximum positioning error from 55h to 80h is 2.59 n mile; after 80h, the maximum positioning error and RMS of the three-point correction algorithm are 1.00 n mile and 0.70 n mile, respectively.

[0088] In summary, at 55h - 80h, the navigation and positioning accuracy of the damping switching combined with the two-point correction is better than that of the damping switching combined with the three-point correction. After 80h, the navigation and positioning accuracy of the damping switching combined with the two-point correction is worse than that of the damping switching combined with the three-point correction. Therefore, in the complex sea conditions of the deep and far sea, combining the advantages of both, the present invention proposes a combined navigation comprehensive correction method based on intelligent damping switching, which performs two-point correction when two-point correction is satisfied and three-point correction when three-point correction is satisfied.

[0089] Refer to Figure 6 , Figure 6 Figure is the comparison chart of the positioning errors of the three navigation and positioning methods in Experiment 3. Figure 6 In, "pure inertial navigation" represents navigation and positioning based on pure inertial navigation, "traditional method" represents navigation and positioning using the traditional damping switching algorithm, and "method of this paper" represents the combined navigation comprehensive correction method based on intelligent damping switching proposed by the present invention. It can be seen from Figure 6 that the combined navigation comprehensive correction method based on intelligent damping switching is superior to the "pure inertial navigation" and the "traditional method". Using the combined navigation comprehensive correction method based on intelligent damping switching, two-point correction is performed at 55h and three-point correction is performed at 80h during the submersible's navigation; the navigation and positioning results output by the two-point correction are in the interval from 55h to 80h, and the navigation and positioning results output by the three-point correction are after 80h, with the smallest positioning error among the two.

[0090] The combined navigation comprehensive calibration method based on intelligent damping switching proposed by the present invention combines the advantages of fault-tolerant damping switching two-point calibration and fault-tolerant damping switching three-point calibration, and has the highest positioning accuracy.

[0091] Facing the complex sea conditions of long-term navigation in the deep and far seas, compared with the traditional fixed threshold of damping switching, an artificial neural network is introduced in this paper to select the threshold online in real time to achieve damping switching. When the submersible is on a mission, the number of surfacing times cannot be determined. The traditional method only realizes a single two-point calibration or three-point calibration. The present invention comprehensively calibrates by making the most efficient use of valid points according to the number of valid points of the actual calibration points. The damping switching algorithm improves the short-term accuracy of navigation and positioning, and the comprehensive calibration improves the long-term accuracy of navigation and positioning. The present invention conducts comprehensive calibration on the basis of intelligent damping switching for typical mission scenarios, combines the advantages of both intelligent damping switching and intelligent comprehensive calibration, and improves the short-term and long-term accuracy of navigation and positioning.

[0092] On the other hand, the present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the combined navigation comprehensive calibration method based on intelligent damping switching provided in any of the above embodiments are implemented. The computer device may be a server. The computer device includes a processor, a memory, a network interface, and a database 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, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store sample data. The network interface of the computer device is used to communicate with an external terminal through a network connection.

[0093] On the other hand, the present invention provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the combined navigation comprehensive calibration method based on intelligent damping switching provided in any of the above embodiments are implemented.

[0094] 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 the present application can include non-volatile and / or volatile memories. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory 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 (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0095] Matters not covered by this invention are well-known techniques.

[0096] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of 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.

[0097] The above-described embodiments merely represent several implementation manners of the present application. Their descriptions are relatively specific and detailed, but they should not be construed as limiting 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 belong to the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

[0098] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A combined navigation integrated calibration method based on intelligent damping switching, characterized in that Including: During the navigation of the submersible, based on the damping algorithm, output the navigation and positioning result of the current fault-tolerant damping; When satellite signals can be acquired, select different calibration methods to calibrate the navigation and positioning result of the current fault-tolerant damping, and output the calibrated navigation and positioning result, including: When the satellite reference point is acquired for the first time, perform position reset, and the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset; For the subsequently acquired satellite reference points, first judge whether the current satellite reference point is a valid point according to the failure point criterion. If the current satellite reference point is a failure point, perform position reset, and the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect; if a currently acquired satellite reference point is a valid point, the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, improving the short-term positioning effect; if two consecutive currently acquired satellite reference points are valid points, on the premise of position reset, further estimate and compensate the equivalent azimuth gyro drift, and perform two-point calibration to calibrate the navigation and positioning result of the current fault-tolerant damping, and output the navigation and positioning result after two-point calibration, improving the long-term positioning accuracy; if three consecutive currently acquired satellite reference points are valid points, on the premise of position reset, further estimate and compensate the equivalent azimuth gyro drift and the horizontal gyro drift, and perform three-point calibration to calibrate the navigation and positioning result of the current fault-tolerant damping, and output the navigation and positioning result after three-point calibration, improving the long-term positioning accuracy, where the satellite reference points are judged according to the failure point criterion, and the method is: Calculate the matrix corresponding to the current satellite reference point based on the satellite observation matrix and the state transition matrix : Among them represents the state transition matrix from the time when the satellite reference point was obtained last time to the time when the satellite reference point is obtained currently , and , respectively represent the time and the satellite observation matrix at that time; Calculate the matrix corresponding to the current satellite reference point of the condition number ; Matrix corresponding to the current satellite reference point condition number If the condition number is greater than the set threshold, it is considered that the condition number is too large, and the matrix corresponding to the current satellite reference point is prone to singularity, the gyro drift result appears abnormal, and the current satellite reference point is a failure point; otherwise, the current satellite reference point is a valid point.

2. The combined navigation comprehensive calibration method based on intelligent damping switching according to claim 1, wherein, During the navigation of the submersible, real-time acquire the measurement residual of the current Doppler tester and input it into the pre-trained damping switching threshold prediction model based on the artificial neural network to predict the damping switching threshold online in real time and achieve damping switching.

3. The integrated calibration method for integrated navigation based on intelligent damping switching according to claim 2, wherein Add different classical noises to the Doppler tester respectively, including step noise, periodic oscillation noise, ramp noise, ramp sine noise, and perform chi-square detection on the navigation data of the Doppler tester after adding different classical noises; Use the K-means method to classify the chi-square detection results of the navigation data of the Doppler tester after adding different classical noises, and obtain the clustering centers under different classical noises as the expected chi-square detection thresholds under the corresponding classical noises; Use the measurement residuals of the Doppler tester corresponding to the navigation data of the Doppler tester after adding different classical noises as input data, and the expected chi-square detection thresholds under different classical noises as labels to train the constructed artificial neural network to obtain the trained damping switching threshold prediction model based on the artificial neural network.

4. Integrated correction device for integrated navigation based on intelligent damping switching, characterized in that Including: The first module is used to output the navigation and positioning result of the current fault-tolerant damping based on the damping algorithm during the navigation of the submersible; The second module is used to select different calibration methods to calibrate the navigation and positioning result of the current fault-tolerant damping when satellite signals can be acquired, and output the calibrated navigation and positioning result, including: When the satellite reference point is acquired for the first time, only perform position reset, and the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset; For the next obtained satellite reference point, first determine whether the current satellite reference point is a valid point according to the failure point criterion. If the current satellite reference point is a failure point, perform position reset. The currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, which improves the short-term positioning effect. If the currently obtained satellite reference point is a valid point, the currently output navigation and positioning result is the navigation and positioning result of the fault-tolerant damping after position reset, which improves the short-term positioning effect. If two consecutive satellite reference points are currently obtained as valid points, on the premise of position reset, further estimate and compensate for the equivalent azimuth gyro drift, and perform two-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after two-point calibration, which improves the long-term positioning accuracy. If three consecutive satellite reference points are currently obtained as valid points, on the premise of position reset, further estimate and compensate for the equivalent azimuth gyro drift and the horizontal gyro drift, and perform three-point calibration to correct the current navigation and positioning result of the fault-tolerant damping, and output the navigation and positioning result after three-point calibration, which improves the long-term positioning accuracy. Among them, the satellite reference point is judged according to the failure point criterion, and the method is as follows: Calculate the matrix corresponding to the current satellite reference point based on the satellite observation matrix and the state transition matrix : Among them represents the state transition matrix from the time when the satellite reference point was obtained last time to the time when the satellite reference point is obtained currently , and , respectively represent the time and the satellite observation matrix at that time; Calculate the matrix corresponding to the current satellite reference point of the condition number ; Matrix corresponding to the current satellite reference point condition number of When it is greater than the set threshold, it is considered that the condition number is too large, and the matrix corresponding to the current satellite reference point is prone to singularity, the gyro drift result appears abnormal, and the current satellite reference point is a failure point; otherwise, the current satellite reference point is a valid point.

5. A computer device, comprising a memory and a processor, the memory storing a computer program, characterized in that, When the processor executes the computer program, it realizes the steps of the combined navigation comprehensive calibration method based on intelligent damping switching as described in claim 1.

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