An inertial navigation method, system, device and medium for a deep-sea underwater unmanned vehicle

Abstract

The present invention relates to the technical field of UUV navigation, and particularly to an inertial navigation method, system, device and medium for a deep-sea underwater unmanned vehicle, including: after the combined navigation system passes the self-check, deploying the underwater unmanned vehicle and initial aligning it using the position information output by the satellite positioning device, detecting whether the fiber optic inertial navigation system receives a calibration instruction. If the calibration instruction is not received, after the fiber optic inertial navigation system is successfully initially aligned, enter the task-only execution working condition and obtain the optimal estimation of the navigation parameters. If the calibration instruction is received, after the fiber optic inertial navigation system is successfully initially aligned, according to whether the underwater unmanned vehicle needs to execute a task, enter the calibration and task execution working condition or the calibration-only working condition respectively. The present invention solves the working timing problem of the INS during the whole process of the large-depth UUV from deployment, underwater task execution to recovery by dividing into three situations: only task execution, task execution after calibration, and only calibration required.

Description

Technical Field

[0001] The present invention relates to the technical field of UUV navigation, and particularly to an inertial navigation method, system, device and medium for a deep-sea unmanned underwater vehicle. Background Art

[0002] At present, most unmanned underwater vehicles (UUVs) are equipped with inertial navigation systems (INSs) based on fiber optic / laser gyroscopes. Since the diving depth of UUVs generally does not exceed 1000 m, the navigation methods adopted by the inertial navigation systems are relatively simple, and usually the methods of combining INS and doppler velocity log (DVL) or INS and global navigation satellite system (GNSS) are used.

[0003] However, GNSS information can only be received when the UUV floats to the water surface or near the water surface, and it is not applicable to large-depth UUVs with a diving depth exceeding 1000 m. Existing INS navigation methods are also not applicable to large-depth UUVs. For example, when the working depth exceeds 6000 meters, the requirements for the navigation accuracy of UUVs and other aspects will be more stringent. Summary of the Invention

[0004] The present invention provides an inertial navigation method, system, device and medium for a deep-sea unmanned underwater vehicle, and the technical problem to be solved is that traditional unmanned underwater vehicles equipped with inertial navigation systems cannot be applied to deep sea areas and have poor navigation accuracy.

[0005] To solve the above technical problems, the present invention provides an inertial navigation method, system, device and medium for a deep-sea unmanned underwater vehicle.

[0006] In a first aspect, the present invention provides an inertial navigation method for a deep-sea unmanned underwater vehicle, which is applied to a combined navigation system installed on the unmanned underwater vehicle. The combined navigation system includes a fiber optic inertial navigation system, a satellite positioning device, a doppler velocity log and a depth gauge. The satellite positioning device includes a satellite positioning receiver and an underwater acoustic positioning system. The method includes the following steps:

[0007] Perform self-check on the combined navigation system, and deploy the unmanned underwater vehicle after the self-check passes;

[0008] Start initial alignment using the position information output by the satellite positioning device, and detect whether the fiber optic inertial navigation system receives a calibration instruction. If the calibration instruction is not received, after the initial alignment of the fiber optic inertial navigation system is successful, enter the working condition of only executing tasks to complete combined navigation;

[0009] If a calibration instruction is received, after the initial alignment of the fiber optic inertial navigation system is successful, it is determined whether the underwater unmanned vehicle needs to perform a task. If it needs to perform a task, it enters the calibration and task execution working condition to complete integrated navigation; otherwise, it enters the only calibration working condition;

[0010] After the navigation mission is completed, the optimal estimation of the navigation parameters is obtained.

[0011] In a further implementation, the only task execution working condition includes:

[0012] Receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point;

[0013] Use the position information of the satellite positioning receiver to perform water surface calibration at the diving point. After the water surface calibration at the diving point is completed, control the underwater unmanned vehicle to start diving;

[0014] Perform integrated navigation solution according to the position information of the satellite positioning device to obtain the optimal estimation of the navigation parameters;

[0015] When the navigation mission is completed, the underwater unmanned vehicle floats to the water surface for positioning and recovery to complete integrated navigation.

[0016] In a further implementation, the only calibration working condition includes:

[0017] Calibrate the fiber optic inertial navigation system using the position information output by the satellite positioning device and the speed information output by the Doppler velocimeter, and perform secondary alignment of the fiber optic inertial navigation system on the water surface;

[0018] After the calibration is completed, recover the underwater unmanned vehicle.

[0019] In a further implementation, the calibration and task execution working condition includes:

[0020] Calibrate the fiber optic inertial navigation system using the position information output by the satellite positioning device and the speed information output by the Doppler velocimeter, and after the calibration is completed, perform secondary alignment of the fiber optic inertial navigation system on the water surface;

[0021] After the secondary alignment is completed, receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point;

[0022] Use the position information of the satellite positioning receiver to perform water surface calibration at the diving point. After the water surface calibration at the diving point is completed, control the underwater unmanned vehicle to start diving;

[0023] Perform integrated navigation solution according to the position information of the satellite positioning device to obtain the optimal estimation of the navigation parameters;

[0024] When completing the navigation mission, the underwater unmanned vehicle floats to the water surface for positioning and recovery, and completes integrated navigation.

[0025] In a further embodiment, the step of performing integrated navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters includes:

[0026] Collect the integrated navigation information output by the integrated navigation system; wherein, the integrated navigation information includes the angular velocity information and acceleration information output by the fiber optic inertial navigation system, the position information output by the underwater acoustic positioning system, the velocity information output by the Doppler velocimeter, and the depth information output by the depth gauge;

[0027] Based on the linear Kalman model, use the integrated navigation information to calibrate the fiber optic inertial navigation system underwater;

[0028] Use the integrated navigation information to perform integrated navigation solution and correct the error of the integrated navigation system to obtain the optimal estimation of navigation parameters; wherein, the optimal estimation of navigation parameters includes the real-time velocity, position, and attitude of the fiber optic inertial navigation system.

[0029] In a further embodiment, when calibrating the fiber optic inertial navigation system underwater using the integrated navigation information, the state space model of the integrated navigation system is:

[0030]

[0031] Wherein,

[0032]

[0033]

[0034] In the formula, X k represents the n-dimensional state vector of the integrated navigation system at time k; Φ k，k-1 represents the state transition matrix from time (k - 1) to time k; Γ k，k-1 represents the noise distribution matrix from time (k - 1) to time k; W k-1 represents the system noise vector; Z k represents the observation vector at time k; H k represents the observation matrix at time k; V k represents the observation noise vector at time k; λ UAPS represents the longitude output by the underwater acoustic positioning system; L UAPS represents the latitude output by the underwater acoustic positioning system; h DG represents the depth information output by the depth gauge; λ INS represents the longitude output by the fiber optic inertial navigation system; LINS represents the latitude output by the fiber optic inertial navigation system; h INS represents the depth information output by the fiber optic inertial navigation system.

[0035] In a further embodiment, the fiber optic inertial navigation system includes a three-axis fiber optic gyroscope assembly, a quartz flexure accelerometer, an I / F conversion current, a DC power supply, a navigation computer, and navigation software;

[0036] wherein, the navigation computer includes an FPGA, a DSP, an ARM, and a power supply module, and the navigation computer is used to periodically collect the position information output by the satellite positioning device and the speed information output by the Doppler velocimeter through two RS422 interfaces;

[0037] The FPGA is used to receive the digital quantity signals output by the fiber optic inertial navigation system and the temperature sensor through two I / O isolation signal lines and one RS422 interface, and trigger the DSP external interrupt;

[0038] The DSP is used to read and perform navigation solution using the digital quantity signals collected by the FPGA, and return the optimal estimation of the navigation parameters after the solution to the FPGA through the interrupt method.

[0039] In a second aspect, the present invention provides an inertial navigation system for a deep-sea underwater unmanned vehicle, and the system includes:

[0040] A system self-check module, which is used to perform self-check on the integrated navigation system, and deploy the underwater unmanned vehicle after the self-check passes;

[0041] An initial alignment module, which is used to start initial alignment using the position information output by the satellite positioning device, and detect whether the fiber optic inertial navigation system receives a calibration instruction. If the calibration instruction is not received, after the initial alignment of the fiber optic inertial navigation system is successful, it enters the working condition of only executing tasks to complete the integrated navigation;

[0042] A task judgment module, which is used to, if a calibration instruction is received, after the initial alignment of the fiber optic inertial navigation system is successful, judge whether the underwater unmanned vehicle needs to execute a task. If it needs to execute a task, it enters the calibration and task execution working condition to complete the integrated navigation; otherwise, it enters the only calibration working condition;

[0043] A data output module, which is used to obtain the optimal estimation of the navigation parameters after the navigation mission is completed.

[0044] In a third aspect, the present invention further provides a computer device, including a processor and a memory, the processor is connected to the memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the computer device executes the steps to implement the above method.

[0045] In a fourth aspect, the present invention further provides a computer-readable storage medium, in which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method are implemented.

[0046] The present invention provides a deep-sea underwater unmanned vehicle inertial navigation method, system, device and medium. By dividing into three situations: only performing tasks, performing tasks after calibration, and only requiring calibration, the method solves the working timing problem of the INS during the whole process from the deployment, underwater task execution to recovery of a large-depth UUV. Compared with the prior art, this method proposes a combined navigation scheme and its combined navigation algorithm for the inertial navigation of large-depth UUVs, and configures a navigation computer design scheme, which not only considers the navigation of large-depth underwater unmanned vehicles, but also can perform calibration and task execution for different situations; in addition, the navigation computer provided by the present invention has the advantages of high integration, small volume, low power consumption, etc., improving the navigation accuracy and adaptability to complex environments, and having broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a schematic flow chart of the deep-sea underwater unmanned vehicle inertial navigation method provided by an embodiment of the present invention;

[0048] Figure 2 is a schematic diagram of the combined navigation system provided by an embodiment of the present invention;

[0049] Figure 3 is a schematic diagram of the hardware structure of the navigation computer provided by an embodiment of the present invention;

[0050] Figure 4 is a schematic diagram of the working timing of the INS only performing tasks provided by an embodiment of the present invention;

[0051] Figure 5 is a schematic diagram of the working timing of the INS only for calibration provided by an embodiment of the present invention;

[0052] Figure 6 is a schematic diagram of the working timing of the INS for calibration and task execution provided by an embodiment of the present invention;

[0053] Figure 7 is a schematic diagram of the electrical connection structure of the combined navigation system provided by an embodiment of the present invention;

[0054] Figure 8 is a schematic diagram of the working process of the INS provided by an embodiment of the present invention;

[0055] Figure 9 is a schematic diagram of the inertial navigation combined navigation principle of the INS provided by an embodiment of the present invention;

[0056] Figure 10It is the INS integrated navigation flow chart provided by the embodiments of the present invention;

[0057] Figure 11 It is the block diagram of the inertial navigation system of the deep-sea underwater unmanned vehicle provided by the embodiments of the present invention;

[0058] Figure 12 It is the structural schematic diagram of the computer device provided by the embodiments of the present invention. Specific embodiments

[0059] The following specifically illustrates the embodiments of the present invention in conjunction with the accompanying drawings. The given embodiments are only for illustrative purposes and should not be construed as limiting the present invention. The accompanying drawings are only for reference and illustration and do not constitute a limitation on the protection scope of the present invention's patent, because many changes can be made to the present invention without departing from the spirit and scope of the present invention.

[0060] Reference Figure 1 , the embodiments of the present invention provide a deep-sea underwater unmanned vehicle inertial navigation method, as Figure 1 shown, the method includes the following steps:

[0061] S1. Self-check the integrated navigation system, and after the self-check passes, deploy the underwater unmanned vehicle.

[0062] In this embodiment, the integrated navigation system controls the underwater unmanned vehicle to power on, and after separately self-checking the fiber optic inertial navigation system (INS), satellite positioning device (GNSS), and Doppler velocity log (DVL) in the integrated navigation system, deploy the underwater unmanned vehicle (UUV) on the shore or the mother ship. When the UUV is deployed on the shore surface, initial alignment is performed in the floating state on the water surface; when it is deployed on the mother ship, the UUV is transported by the mother ship to the predetermined sea area. After arrival, the mother ship is in a floating state, and initial alignment is performed on the mother ship.

[0063] Such as Figure 2As shown, the deep-sea underwater unmanned vehicle applied in this embodiment includes an integrated navigation system installed on the underwater unmanned vehicle, and the integrated navigation system includes a fiber optic inertial navigation system (INS), a satellite positioning device (GNSS), a Doppler velocity log (DVL), a depth meter and a host computer; wherein the fiber optic inertial navigation system is the hub and core of the entire integrated navigation system, and the fiber optic inertial navigation system includes a three-axis fiber optic gyroscope combination, a quartz flexible accelerometer, an I / F conversion current, a DC power supply, a navigation computer and navigation software; the satellite positioning device includes a satellite positioning receiver and an underwater acoustic positioning system. In this embodiment, the satellite positioning system (global navigation satellite system, GNSS) and the Doppler velocity log (DVL) can be mature off-the-shelf products. At the same time, considering the future compatibility with the Beidou satellite navigation solution, a satellite navigation chip compatible with Beidou / GPS is selected as a positioning information reference.

[0064] Among them, such as Figure 3 As shown, the navigation computer includes FPGA, DSP, ARM, crystal oscillator, JTAG, SDRAM, FLASH and power module. It should be noted that traditional computer hardware adopts a hardware structure combining FPGA, DSP and FLASH, while this embodiment adopts a hardware structure combining FPGA, DSP, ARM, DDR and two FLASH. The hardware structure of this embodiment has improved performance indicators such as data processing efficiency, processing speed, reading and storage speed, storage reliability, and storage capacity. The hardware structure function of the navigation computer provided by this embodiment is described as follows:

[0065] (1) Regularly collect digital signals from satellite positioning device (GPS / Beidou two-in-one) and Doppler velocimeter (DVL) through two RS422 interfaces;

[0066] (2) Receive digital signals from the inertial measurement unit (IMU) (including three gyroscopes, three accelerometers, and a temperature sensor) through two I / O isolation signal lines and one RS422 interface;

[0067] (3) The expansion board is used for information collection and packaging transmission of external inertial navigation sources, and the core board is used for receiving and processing external signals (external inertial navigation sources and external information sources) (including initial alignment, navigation parameter solution and integrated navigation, etc.), and outputting the processed navigation information to the carrier through the serial port;

[0068] (4) It has the function of storing and downloading the original data of the external inertial navigation source, the original data of the external information source, and the calculated navigation information data; after the FPGA collects the output data of the sensors (including the data of three gyroscopes, three accelerometers, and temperature sensors) and preprocesses it to obtain the original data, it sends instructions such as interrupts to the DSP to let the DSP read the data. The DSP reads the original data from the FPGA and stores it in the DDR2 (temporary storage). The ARM reads the DE1 original data in the DDR2 and stores it in the FLASH-1 (permanent storage). The DSP uses the original data for navigation calculation, stores the obtained navigation information in the synchronous dynamic random access memory, and the ARM stores it in the FLASH-1. The specific content stored in each memory is as follows: FLASH-1 stores the programs running in the DSP and ARM, original data, instruction information, and navigation information. The DDR2 is used for temporarily storing the original data and navigation information. The FLASH-2 stores the program running in the FPGA. The network port is used for updating the program, downloading the original data, instruction information, and navigation information;

[0069] (5) Power supply voltage: The power supply module converts the input 28V voltage into the power supply voltages required by each module, mainly including the following voltages: +5V, ±5V, and ±15V. The core board and the expansion board input +5V voltage, and the power management circuits on their respective boards convert it into the required voltages; the voltages required by the ring laser gyroscope, accelerometer, and temperature sensor are ±5V, ±15V, and +5V respectively;

[0070] (6) The DSP, ARM, and FPGA chips are debugged through the JTAG interface and the network port.

[0071] It should be noted that in Figure 3 , the "debugging computer" in the dotted box represents the device that needs to be connected only when debugging or downloading data on the shore. The navigation computer does not need to be debugged when the carrier is working underwater.

[0072] In this embodiment, the navigation software is an important part of the integrated navigation system. The host computer circuit of the software is the navigation computer. The navigation software is solidified in the Flash of the computer. After the computer is powered on, the navigation software is loaded into the SRAM for operation. The navigation software is used to implement functions such as internal timing management of integrated navigation, data acquisition of fiber optic gyroscopes and accelerometers, error model calculation, navigation calculation, and communication with shipborne computers or test equipment. The function description of the navigation software is as follows:

[0073] a) Initialization of the navigation computer circuit; after the integrated navigation is powered on and started, the software needs to complete the initialization of the navigation computer circuit, including: various configurations of the DSP, initialization of the communication ports of the fiber optic gyroscopes, initialization of the communication ports on carriers such as UUVs, and timer settings.

[0074] b) Data acquisition; The data acquisition period is 5 ms. The data collected by the software includes the data of three fiber optic gyroscopes and three quartz flexible accelerometers.

[0075] c) Error model compensation calculation; After the navigation software completes data acquisition, it calculates according to the error compensation model to obtain the angular increment and velocity increment of this period.

[0076] d) Complete navigation solution; The software completes the real-time update of the attitude according to the navigation solution algorithm and the attitude correction algorithm, and at the same time completes the calculation of the angular rate of the corresponding attitude.

[0077] e) Communicate with the integrated control computer and test equipment of the vehicle; The communication mode between the integrated navigation and the integrated control computer and the test system of the vehicle is two-way. The integrated navigation adopts different data sending methods according to different data requests of the computer on the mine or the test equipment.

[0078] f) Program and parameter update; The navigation software can realize the online upgrade of the software and the update of the error compensation parameters. It receives the file sent by the test system through the communication port and writes the file into the Flash to realize the online upgrade of the navigation software or the parameter update.

[0079] g) The INS / GNSS / DVL integrated navigation receiver receives the position information of GNSS through the internal satellite receiver and receives the velocity information of DVL through the external serial interface. On the basis of inertial navigation, it judges the validity of the information, uses the effective external auxiliary information for integrated navigation settlement, corrects the error of the integrated navigation system, suppresses the growth of the error of the integrated navigation system, and corrects the DVL error when conditions permit to improve the integrated navigation accuracy of the vehicle underwater.

[0080] Specifically, the working process of the navigation software is as follows: After the integrated navigation system is powered on and started, the DSP loads the navigation software from the Flash into the SRAM and starts running. After the navigation software completes the hardware initialization, it enters the real-time working mode, that is, it collects gyroscope and accelerometer data every 5 ms and performs compensation calculations, while waiting for external commands. When an external command arrives, according to the received command, it starts tasks such as navigation solution, data transmission, parameter update, and program update. The software is divided into three relatively independent parts: the main program, the timer interrupt subroutine, and the external command interrupt processing subroutine. The main program completes tasks such as software and hardware initialization, timer setting, gyroscope data acquisition, accelerometer data acquisition, compensation calculation, navigation solution, attitude correction, error correction, and fault diagnosis; the timer interrupt subroutine completes the operations of the gyroscope and accelerometer data acquisition flags; the external command interrupt processing subroutine completes tasks such as command recognition, parsing, and data transmission; the navigation software includes the lower layer and the upper layer. The lower layer software includes the acquisition, preprocessing (such as filtering), storage, reading, and transmission of sensor data, the processing of flag bits, the interrupts, I / O, reset, chip select signals, read / write control, etc. between chips; the upper layer software mainly includes the navigation software running in the FPGA and the DSP.

[0081] S2. Start initial alignment using the position information output by the satellite positioning device, and detect whether the fiber optic inertial navigation system receives a calibration command. If the calibration command is not received, after the initial alignment of the fiber optic inertial navigation system is successful, enter the mission-only execution mode to complete the integrated navigation.

[0082] In one embodiment, as Figure 4 shown, the mission-only execution mode includes:

[0083] Receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point;

[0084] Use the position information of the satellite positioning receiver to perform water surface calibration at the diving point. After the water surface calibration at the diving point is completed, control the underwater unmanned vehicle to start diving;

[0085] Perform integrated navigation solution according to the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters;

[0086] When the navigation mission is completed, the underwater unmanned vehicle floats to the water surface and performs positioning and recovery to complete the integrated navigation.

[0087] Specifically, as Figure 4As shown in the figure, during the alignment process of this embodiment, it is detected in real time whether a calibration instruction is received. Before the calibration instruction is not received or the fiber optic inertial navigation system (INS) has been calibrated and does not need to be recalibrated, the fiber optic inertial navigation system only performs tasks, that is, after the initial alignment is successful, it receives the position information of the satellite positioning receiver for integrated navigation. After the UUV reaches the predetermined diving point under the control of the operator or the mother ship, the central control unit of the UUV issues an instruction to start executing the navigation mission task, and the fiber optic inertial navigation system (INS) starts to execute the navigation mission task. Specifically: The fiber optic inertial navigation system uses the position information of the satellite positioning receiver to perform pre-dive surface calibration. After the pre-dive surface calibration is completed, it controls the UUV to start diving. After the UUV reaches the predetermined depth, it starts to execute the navigation mission task. After the navigation mission task ends, the UUV surfaces. After the UUV reaches the water surface, it uses devices such as GNSS or strobe lights for positioning.

[0088] It should be noted that when the fiber optic inertial navigation system only performs tasks, Figure 4 The upward solid double arrow in the figure indicates a process that definitely exists, and the upward dotted arrow indicates a process that may exist. If the occurrence time (relative time value) of each process or the time interval between processes is not given, it means an uncertain time or time interval; in addition, during the underwater cruise process, there will be a situation where the DVL's acoustic wave cannot detect the seabed. If the DVL is in this state for a long time, the accuracy of the INS will approach the pure inertial navigation accuracy; this embodiment takes a large-depth AUV as an example, which is in the pure inertial navigation state during diving. For a small-depth AUV, it is generally in the integrated navigation state during diving.

[0089] S3. If a calibration instruction is received, after the initial alignment of the fiber optic inertial navigation system is successful, it is judged whether the underwater unmanned vehicle needs to perform tasks. If it needs to perform tasks, it enters the calibration and task execution working condition to complete integrated navigation; otherwise, it enters the only calibration working condition.

[0090] Specifically, during the initial alignment process of this embodiment, if it is detected that the fiber optic inertial navigation system receives a calibration instruction, after the initial alignment of the fiber optic inertial navigation system is successful, the INS starts to perform calibration. After the calibration is completed, there are two situations:

[0091] The first: It does not need to perform tasks near the end of the calibration voyage and only needs calibration. The timing diagram of the INS's only calibration work is shown in Figure 5 ; It should be noted that when the UUV is recovered and the task is executed again, the whole process is executed according to the only task execution process;

[0092] The second: It needs to perform tasks near the end of the calibration voyage, then continue to perform tasks according to the above situation where the fiber optic inertial navigation system only performs tasks, specifically as shown in Figure 6 shown.

[0093] In one embodiment, as Figure 5 shown, the only calibration condition includes:

[0094] Calibrate the fiber optic inertial navigation system using the position information output by the satellite positioning device and the velocity information output by the Doppler velocimeter, and perform a secondary alignment on the water surface for the fiber optic inertial navigation system;

[0095] After calibration is completed, recover the underwater unmanned vehicle.

[0096] In one embodiment, as Figure 6 shown, the calibration and mission execution condition includes:

[0097] Calibrate the fiber optic inertial navigation system using the position information output by the satellite positioning device and the velocity information output by the Doppler velocimeter, and after calibration is completed, perform a secondary alignment on the water surface for the fiber optic inertial navigation system;

[0098] After the secondary alignment is completed, receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point;

[0099] Perform surface calibration of the diving point using the position information of the satellite positioning receiver, and after the surface calibration of the diving point is completed, control the underwater unmanned vehicle to start diving;

[0100] Perform integrated navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters;

[0101] When the navigation mission is completed, the underwater unmanned vehicle floats to the water surface and performs positioning and recovery to complete integrated navigation.

[0102] In one embodiment, the step of performing integrated navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters includes:

[0103] Collect the integrated navigation information output by the integrated navigation system; wherein, the integrated navigation information includes the angular velocity information and acceleration information output by the fiber optic inertial navigation system, the position information output by the underwater acoustic positioning system, the velocity information output by the Doppler velocimeter, and the depth information output by the depth gauge;

[0104] Based on the linear Kalman model, calibrate the fiber optic inertial navigation system underwater using the integrated navigation information;

[0105] Perform integrated navigation solution using the integrated navigation information and correct the error of the integrated navigation system to obtain the optimal estimation of navigation parameters; wherein, the optimal estimation of navigation parameters includes the real-time velocity, position, and attitude of the fiber optic inertial navigation system.

[0106] In this embodiment, when the large-depth UUV performs underwater operations, this embodiment adopts an underwater calibration algorithm based on an underwater acoustic positioning system. Among them, the state space model of the integrated navigation system is as follows:

[0107]

[0108] Among them,

[0109]

[0110] When underwater calibration is performed, the inertial navigation is in the combined mode of INS, underwater acoustic positioning system (UAPS), and depth gauge (DG). Z k and H k are respectively:

[0111]

[0112]

[0113] In the formula, X k represents the n-dimensional state vector of the integrated navigation system at time k. Among them, φ E , φ N , φ U respectively represent the attitude errors in the east, north, and sky directions. δv E , δv N , δv U respectively represent the velocity errors in the east, north, and sky directions. δλ, δL, and δh respectively represent the errors in longitude, latitude, and altitude. ε E , ε N , ε U respectively represent the gyro constant drift errors in the east, north, and sky directions. respectively represent the accelerometer zero bias errors in the east, north, and sky directions; Φ k，k-1 represents the state transition matrix from time (k - 1) to time k; Γ k，k-1 represents the noise distribution matrix from time (k - 1) to time k; W k-1 represents the system noise vector; Z k represents the observation vector at time k; H k represents the observation matrix at time k; V k represents the observation noise vector at time k. W k-1 , V k are both zero-mean Gaussian white noise vector sequences and are uncorrelated with each other; λ UAPS represents the longitude output by the underwater acoustic positioning system; LUAPS represents the latitude output by the underwater acoustic positioning system; h DG represents the depth information output by the depth gauge; λ INS represents the longitude output by the fiber optic inertial navigation system; L INS represents the latitude output by the fiber optic inertial navigation system; h INS represents the depth information output by the fiber optic inertial navigation system.

[0114] It should be noted that for the underwater calibration situation in this embodiment, the position information is sourced from the underwater acoustic positioning system of the mother ship. Meanwhile, in this embodiment, after the alignment is completed, before the integrated navigation starts, or during the integrated navigation process, the INS can be calibrated several times using GNSS. When debugging the INS in the absence of GNSS signals (for example: debugging the inertial navigation in a workshop or laboratory), the position information can be sent by the central control unit to assist the INS in completing the alignment.

[0115] Figure 7 Describes the electrical connection relationship of the integrated navigation system of the entire UUV. The INS is the center and core of the integrated navigation system. The debugging computer is only used to connect to the INS during onshore debugging. The GNSS includes two parts: the GNSS above-water unit and the GNSS underwater unit. The UUV system includes two parts: the UUV vehicle body and the centralized control system. The centralized control system is placed on the mother ship to control the UUV. The main body of the centralized control system includes an industrial control computer and the GNSS above-water unit. The GNSS underwater unit is installed on the UUV. The GNSS above-water unit and the GNSS underwater unit communicate with each other via satellite (the short message function of Beidou-1).

[0116] S4. After completing the navigation mission, obtain the optimal estimation of the navigation parameters.

[0117] Specifically, in this embodiment, as Figure 8 、 9 、shown in 10, the working process of the integrated navigation system includes the power-on self-check, alignment, and integrated navigation phases. Among them, during the power-on self-check process, the integrated navigation system checks for faults in the system. When a fault is detected, the corresponding status is set for the fault. If there is no fault in the system, it transfers to the alignment process; during the alignment process, the integrated navigation system uses the satellite positioning information as a reference to obtain the initial attitude of the current integrated navigation system, and then transfers to the integrated navigation process; during the integrated navigation process, the integrated navigation system uses GNSS and DVL information for integrated navigation calculation to obtain information such as the real-time speed, position, and attitude of the inertial navigation.

[0118] This embodiment provides an inertial navigation method for a deep - sea underwater unmanned vehicle. By dividing into three situations: only performing tasks, performing tasks after calibration, and only requiring calibration, and configuring the navigation computer hardware and navigation software, a combined navigation scheme for inertial navigation of large - depth UUVs and its combined navigation algorithm technical solution are realized, solving the working timing problem of INS during the whole process from the deployment, underwater task execution to recovery of large - depth UUVs. Compared with the prior art, this method not only considers the navigation of deep - sea underwater unmanned vehicles, but also can calibrate and perform tasks for different situations; the method provided by the present invention has the advantages of high hardware integration, low power consumption, simple calculation, good real - time performance, etc., improving the combined navigation accuracy and usage flexibility of the underwater navigation system.

[0119] It should be noted that the magnitudes of the sequence numbers of the above - mentioned processes do not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0120] [[ID=⑥]]In one embodiment, as Figure 11 shown, this embodiment provides an inertial navigation system for a deep - sea underwater unmanned vehicle, and the system includes:

[0121] A system self - check module 101, which is used to perform self - check on the integrated navigation system, and after the self - check passes, deploy the underwater unmanned vehicle;

[0122] An initial alignment module 102, which is used to start initial alignment using the position information output by the satellite positioning device, and detect whether the fiber optic inertial navigation system receives a calibration instruction. If the calibration instruction is not received, after the initial alignment of the fiber optic inertial navigation system is successful, enter the working condition of only performing tasks to complete integrated navigation;

[0123] A task judgment module 103, which is used to, if a calibration instruction is received, after the initial alignment of the fiber optic inertial navigation system is successful, judge whether the underwater unmanned vehicle needs to perform a task. If it needs to perform a task, enter the calibration and task - performing working condition to complete integrated navigation; otherwise, enter the only - calibration working condition;

[0124] A data output module 104, which is used to obtain the optimal estimation of navigation parameters after the navigation mission is completed.

[0125] For the specific limitations of an inertial navigation system for a deep - sea underwater unmanned vehicle, reference may be made to the above - mentioned limitations for an inertial navigation method for a deep - sea underwater unmanned vehicle, which will not be elaborated here. Those of ordinary skill in the art can realize that, for each module and step described in combination with the embodiments disclosed in this application, they can be implemented in hardware, software, or a combination of both. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of this application.

[0126] An embodiment of the present invention provides an inertial navigation system for a deep - sea underwater unmanned vehicle. The combined navigation system is self - checked through a system self - check module; the initial alignment of the fiber optic inertial navigation system is achieved through an initial alignment module and a task judgment module, and according to whether a calibration instruction is received, it is divided into three cases: only executing tasks, executing tasks after calibration, and only requiring calibration to complete combined navigation. Compared with the prior art, this application divides into three cases: only executing tasks, executing tasks after DVL calibration, and only requiring calibration, which solves the working timing problem of the INS during the whole process of the large - depth UUV from deployment, underwater task execution to recovery. It can be applied to large - depth underwater unmanned vehicles and at the same time ensures the accuracy of underwater robot navigation.

[0127] Figure 12 This is a computer device provided by an embodiment of the present invention, including a memory, a processor, and a transceiver, which are connected through a bus; the memory is used to store a set of computer program instructions and data, and can transmit the stored data to the processor. The processor can execute the program instructions stored in the memory to execute the steps of the above - mentioned method.

[0128] Among them, the memory may include volatile memory or non - volatile memory, or may include both volatile and non - volatile memory; the processor may be a central processing unit, a microprocessor, an application - specific integrated circuit, a programmable logic device, or a combination thereof. By way of example but not limitation, the above - mentioned programmable logic device may be a complex programmable logic device, a field - programmable gate array, a generic array logic, or any combination thereof.

[0129] In addition, the memory may be a physically independent unit or may be integrated with the processor.

[0130] Those of ordinary skill in the art can understand that Figure 12 the structure shown in

[0131] In one embodiment, an embodiment of 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 method are implemented.

[0132] An inertial navigation method, system, device and medium for a deep-sea underwater unmanned vehicle provided by an embodiment of the present invention. An inertial navigation method for a deep-sea underwater unmanned vehicle overcomes the defect that traditional underwater unmanned vehicles cannot be applied to underwater operations at large depths, ensures the reliability of the navigation system, and has advantages such as low computational complexity and high practical value.

[0133] In the above embodiment, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described in the embodiments of the present invention are generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center in a wired manner (such as coaxial cable, optical fiber, digital subscriber line) or a wireless manner (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more integrated available media. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a magnetic tape), an optical medium (for example, a DVD), or a semiconductor medium (for example, an SSD), etc.

[0134] Those skilled in the art can understand that all or part of the processes in the above embodiment methods can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods.

[0135] The above embodiments only represent several preferred embodiments of the present application. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the protection scope of the claims.

Claims

1. An inertial navigation method for an underwater unmanned vehicle in deep sea, characterized in that, Apply a combined navigation system installed on an underwater unmanned vehicle. The combined navigation system includes an optical fiber inertial navigation system, a satellite positioning device, a Doppler velocimeter, and a depth gauge. The satellite positioning device includes a satellite positioning receiver and an underwater acoustic positioning system. The method includes the following steps: Self-check the combined navigation system, and deploy the underwater unmanned vehicle after the self-check passes. Start initial alignment using the position information output by the satellite positioning device, and detect whether the optical fiber inertial navigation system receives a calibration command. If the calibration command is not received, after the initial alignment of the optical fiber inertial navigation system is successful, enter the mission-only execution mode to complete combined navigation. If the calibration command is received, after the initial alignment of the optical fiber inertial navigation system is successful, determine whether the underwater unmanned vehicle needs to execute a mission. If a mission needs to be executed, enter the calibration and mission execution mode to complete combined navigation; otherwise, enter the calibration-only mode. After completing the navigation mission, obtain the optimal estimation of navigation parameters. Among them, the calibration and mission execution mode includes: Calibrate the optical fiber inertial navigation system using the position information output by the satellite positioning device and the velocity information output by the Doppler velocimeter, and after the calibration is completed, perform a secondary alignment of the optical fiber inertial navigation system on the water surface. After the secondary alignment is completed, receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point. Perform water surface calibration of the diving point using the position information of the satellite positioning receiver. After the water surface calibration of the diving point is completed, control the underwater unmanned vehicle to start diving. Perform combined navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters. When the navigation mission is completed, the underwater unmanned vehicle floats to the water surface for positioning and recovery to complete combined navigation.

2. The inertial navigation method of a deep-sea underwater unmanned vehicle according to claim 1, characterized in that, The mission-only execution mode includes: Receive the position information of the satellite positioning receiver and control the underwater unmanned vehicle to reach the preset diving point. Perform water surface calibration of the diving point using the position information of the satellite positioning receiver. After the water surface calibration of the diving point is completed, control the underwater unmanned vehicle to start diving. Perform combined navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters. When the navigation mission is completed, the underwater unmanned vehicle floats to the water surface for positioning and recovery to complete combined navigation.

3. The inertial navigation method of a deep - sea underwater unmanned vehicle according to claim 1, characterized in that, The calibration-only mode includes: Calibrate the optical fiber inertial navigation system using the position information output by the satellite positioning device and the velocity information output by the Doppler velocimeter, and perform a secondary alignment of the optical fiber inertial navigation system on the water surface. After the calibration is completed, recover the underwater unmanned vehicle.

4. A deep-sea underwater unmanned vehicle inertial navigation method according to claim 1 or 2, characterized in that The step of performing combined navigation solution based on the position information of the satellite positioning device to obtain the optimal estimation of navigation parameters includes: Collect the combined navigation information output by the combined navigation system; among them, the combined navigation information includes the angular velocity information and acceleration information output by the optical fiber inertial navigation system, the position information output by the underwater acoustic positioning system, the velocity information output by the Doppler velocimeter, and the depth information output by the depth gauge. Based on the linear Kalman model, use the combined navigation information to perform underwater calibration of the optical fiber inertial navigation system. Combined navigation solution is performed using combined navigation information, and the errors of the combined navigation system are corrected to obtain the optimal estimation of navigation parameters; wherein, the optimal estimation of navigation parameters includes the real-time speed, position, and attitude of the fiber optic inertial navigation system.

5. The inertial navigation method of a deep-sea underwater unmanned vehicle according to claim 4, characterized in that When calibrating the fiber optic inertial navigation system using combined navigation information, the state space model of the combined navigation system is: Wherein, wherein, represents the n-dimensional state vector of the integrated navigation system at time k; represents the state transition matrix from time (k - 1) to time k; represents the noise distribution matrix from time (k - 1) to time k; represents the system noise vector; represents the observation vector at time k; represents the observation matrix at time k; represents the observation noise vector at time k; represents the longitude output by the underwater acoustic positioning system; represents the latitude output by the underwater acoustic positioning system; represents the depth information output by the depth gauge; represents the longitude output by the fiber optic inertial navigation system; represents the latitude output by the fiber optic inertial navigation system; represents the depth information output by the fiber optic inertial navigation system.

6. The inertial navigation method of a deep-sea underwater unmanned vehicle according to claim 1, characterized in that: The fiber optic inertial navigation system includes a three-axis fiber optic gyroscope assembly, a quartz flexure accelerometer, an I / F conversion current, a DC power supply, a navigation computer, and navigation software; Among them, the navigation computer includes an FPGA, a DSP, an ARM, and a power module. The navigation computer is used to periodically collect the position information output by the satellite positioning device and the speed information output by the Doppler velocimeter through two RS422 interfaces; The FPGA is used to receive the digital quantity signals output by the fiber optic inertial navigation system and the temperature sensor through two I / O isolation signal lines and one RS422 interface, and trigger the external interrupt of the DSP; The DSP is used to read and perform navigation solution using the digital quantity signals collected by the FPGA, and return the optimal estimation of the navigation parameters after the solution to the FPGA through the interrupt mode.

7. An inertial navigation system for an underwater unmanned vehicle in deep sea, characterized in that, Applying the inertial navigation method for deep-sea underwater unmanned vehicles as described in any one of claims 1 to 6, the system includes: A system self-check module for self-checking the combined navigation system, and after the self-check passes, deploying the underwater unmanned vehicle; An initial alignment module for starting initial alignment using the position information output by the satellite positioning device, and detecting whether the fiber optic inertial navigation system receives a calibration instruction. If the calibration instruction is not received, after the initial alignment of the fiber optic inertial navigation system is successful, it enters the working condition of only executing tasks and completes combined navigation; A task judgment module for, if a calibration instruction is received, after the initial alignment of the fiber optic inertial navigation system is successful, judging whether the underwater unmanned vehicle needs to execute a task. If it needs to execute a task, it enters the calibration and task execution working condition and completes combined navigation; otherwise, it enters the only calibration working condition; A data output module for obtaining the optimal estimation of navigation parameters after the navigation mission is completed.

8. A computer device, characterized in that: It includes a processor and a memory. The processor is connected to the memory. The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory so that the computer device executes the method described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: A computer program is stored in the computer-readable storage medium. When the computer program is run, the method described in any one of claims 1 to 6 is implemented.

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