Semi-physical simulation system and method for underwater target detection

Abstract

The invention relates to a semi-physical simulation system and method for underwater target detection, and the system is used for constructing a semi-physical simulation test environment of an underwater glider, and comprises a dynamic motion simulation rotary table which is used for driving the underwater glider to simulate an underwater motion posture; the multi-band underwater acoustic signal simulator is used for performing underwater acoustic signal conversion on the virtual underwater acoustic data and transmitting obtained time domain acoustic signals of all frequencies to the underwater glider through the underwater acoustic signal coupling array; the simulation controller is used for resolving kinematics parameters of the underwater glider by using the first calculation channel, generating a pose control instruction and transmitting the pose control instruction to the dynamic motion simulation turntable; and resolving a radiation noise source of the underwater target by using a second calculation channel, generating virtual underwater sound data of the multi-target azimuth feature, and transmitting the virtual underwater sound data to the multi-band underwater sound signal simulator. According to the invention, the technical problems of high target detection and inspection cost, high technical difficulty and poor inspection precision of the existing underwater glider are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of hardware-in-the-loop simulation, and particularly to a hardware-in-the-loop simulation system and method for underwater target detection. Background Art

[0002] An underwater glider is a new type of underwater robot. Since it obtains propulsion by using net buoyancy and attitude angle adjustment, its energy consumption is extremely low, and it only consumes a small amount of energy when adjusting the net buoyancy and attitude angle. Moreover, it has the characteristics of high efficiency and large endurance (up to thousands of kilometers). Although the sailing speed of the underwater glider is slow, its characteristics such as low manufacturing cost, low maintenance cost, reusable, and large-scale deployable meet the needs of long-term and large-scale ocean exploration. When the underwater glider glides, due to non-powered propulsion, the noise is extremely low, and this important characteristic makes it have great application value in the military.

[0003] The main function of the underwater glider is the underwater target detection function, which searches for, locates, and identifies targets during the gliding process in water. Therefore, testing the underwater target detection ability of the underwater glider has become a key link in evaluating its performance. However, in the existing testing technologies, mainly artificial sound source target testing and marine ship target testing are adopted, and both of the above two testing schemes have inevitable defects:

[0004] (1) Artificial sound source target testing: By deploying an underwater glider to detect a target sound source with known position and underwater acoustic characteristics, so as to test and verify the system function and performance. However, since the underwater glider is completely offline after diving and is greatly affected by meteorological conditions such as sea conditions and ocean currents, the positioning error is large, which further affects the test and inspection results.

[0005] (2) Underwater ship target testing: Deploying an underwater glider to test a real target ship sailing in water, and fishing boats, merchant ships, etc. can be randomly selected as detection targets. However, since the position, route, and underwater acoustic characteristics of the target cannot be determined, it is difficult to design the deployment and path planning of the underwater glider. At the same time, a large amount of cost is required for the detection and inspection with a submarine as the target.

[0006] Therefore, those skilled in the art urgently need a technical solution that can efficiently test the underwater target detection function of the underwater glider. Summary of the Invention

[0007] (1) Technical Problems to be Solved

[0008] In view of the above-mentioned disadvantages and deficiencies of the prior art, the present invention provides a hardware-in-the-loop simulation system and method for underwater target detection, which solves the technical problems of high cost, large technical difficulty, and poor inspection accuracy in the existing underwater glider target detection and inspection.

[0009] (2) Technical Solution

[0010] To achieve the above object, the main technical solutions adopted by the present invention include:

[0011] In a first aspect, an embodiment of the present invention provides a hardware-in-the-loop simulation system for underwater target detection, which is applied to construct a hardware-in-the-loop simulation test environment for an underwater glider. The system includes:

[0012] A dynamic motion simulation turntable for driving the underwater glider to simulate an underwater motion posture;

[0013] A multi-band underwater acoustic signal simulator for performing underwater acoustic characteristic analysis processing and synchronous DAC conversion on the input virtual underwater acoustic data with multi-target azimuth characteristics, obtaining time-domain acoustic signals of at least two frequencies, and transmitting the time-domain acoustic signals of all frequencies to the underwater glider through a preset underwater acoustic signal coupling array;

[0014] A simulation controller for using the configured first calculation channel to solve the kinematic parameters of the underwater glider, generating a pose control instruction with a timestamp and transmitting it to the dynamic motion simulation turntable; and using the configured second calculation channel to solve the radiation noise source of a preset underwater target, generating virtual underwater acoustic data with multi-target azimuth characteristics and transmitting it to the multi-band underwater acoustic signal simulator.

[0015] Optionally, the dynamic motion simulation turntable includes:

[0016] A turntable platform for carrying the underwater glider;

[0017] The turntable platform is provided with a fixing mechanism, and the fixing mechanism is used to fix the underwater glider on the turntable platform;

[0018] A multi-degree-of-freedom dynamic driving mechanism, including a driving motor and a transmission device. The transmission device is respectively connected to the driving motor and the turntable platform, and the transmission device is used to drive the turntable platform to perform a three-degree-of-freedom motion including acceleration change and angular velocity change under the power provided by the driving motor;

[0019] A multi-modal sensor array, including an accelerometer, a resolver, and a multi-axis inclinometer, constituting a motion state closed-loop detection network, and real-time collecting motion state information of the turntable platform including pitch angle error compensation amount, angular velocity compensation parameter, and acceleration dynamic response characteristics.

[0020] Optionally, the multi-band underwater acoustic signal simulator includes:

[0021] An underwater acoustic characteristic analysis module for performing underwater acoustic characteristic analysis processing and synchronous DAC conversion on the input virtual underwater acoustic data with multi-target azimuth characteristics through a preset underwater target acoustic characteristic model, obtaining time-domain acoustic signals of at least two frequencies;

[0022] An underwater acoustic signal coupling array for transmitting time-domain acoustic signals of all frequencies to an underwater glider through configured dual acoustic coupling channels;

[0023] Among them, the mathematical expression of the underwater acoustic signal target acoustic characteristic model is:

[0024]

[0025] In the formula, H(t) represents the output of the time-domain acoustic signal, n represents the number of underwater targets, β i represents the azimuth parameter of the i-th underwater target, τ i represents the time-delay parameter of the i-th underwater target, S(t) represents the radiation noise source of the underwater target, λ i represents the angular frequency of the i-th underwater target, Smac(t) represents the mechanical noise line spectrum, Sprop(t) represents the propeller blade line spectrum, Smodu(t) represents the propeller modulation spectrum, and Sconti(t) represents the continuous noise spectrum.

[0026] Optionally, the dual acoustic coupling channels include:

[0027] A transducer array, connected to the underwater acoustic characteristic analysis module, for converting time-domain acoustic signals with frequencies above 10KHz into spatial acoustic signals and transmitting the spatial acoustic signals to the receiving hydrophone of the underwater glider through a preset propagation medium;

[0028] An optical fiber transmission component, respectively connected to the underwater acoustic characteristic analysis module and the underwater glider, for transmitting time-domain acoustic signals with frequencies below 10KHz to the target detection signal acquisition end of the underwater glider.

[0029] Optionally, the transducer array includes:

[0030] A conditioning circuit for performing signal conditioning including signal power amplification and impedance matching on time-domain acoustic signals with frequencies above 10KHz to obtain time-domain acoustic signals impedance-matched to the preset propagation medium;

[0031] Transducer array elements, connected to the conditioning circuit, for generating and outputting spatial acoustic signals to the propagation medium after docking with the receiving hydrophone through the propagation medium, so that the spatial acoustic signals are transmitted to the receiving hydrophone through the propagation medium.

[0032] Optionally, the simulation controller includes:

[0033] A motion attitude simulation module for solving the kinematic parameters of the underwater glider through the underwater glider kinematic model in the configured first calculation channel, generating pose control commands with timestamps and transmitting them to the dynamic motion simulation turntable;

[0034] An underwater acoustic signal simulation module, configured to solve the radiation noise sources of preset underwater targets through the configured second calculation channel, generate virtual underwater acoustic data with multi-target azimuth characteristics, and transmit it to a multi-band underwater acoustic signal simulator;

[0035] Among them, the mathematical expression of the underwater glider kinematic model is:

[0036]

[0037] In the formula, α represents the angular acceleration of the underwater glider, ω represents the angular velocity of the underwater glider, R represents the equipment change constant of the underwater glider, m represents the mass of the moving mass block of the underwater glider, g represents the acceleration due to gravity, x represents the lateral position of the underwater glider, z represents the depth of the underwater glider, θ represents the pitch angle of the underwater glider, x(t) represents the lateral displacement of the underwater glider, z(t) represents the depth displacement of the underwater glider, ξ represents the time constant, u x represents the lateral control input of the underwater glider, u z represents the depth control input of the underwater glider, T y represents the inertial matrix component in the longitudinal direction of the underwater glider.

[0038] Optionally, the underwater glider kinematic model is encapsulated in the FMU format. The FMU format underwater glider kinematic model includes:

[0039] A model description file, used to store the metadata and information of the underwater glider kinematic model to describe the structure, parameters, and input / output variables of the underwater glider kinematic model;

[0040] A model code file, used to store the code of the underwater glider kinematic model algorithm;

[0041] A binary dynamic library, used to compile the model code file in binary format.

[0042] Optionally, the number of underwater gliders is configured to be at least three, and a time delay device is provided at the target detection signal acquisition end of each underwater glider;

[0043] The time delay device is used to perform time delay processing on the same segment of time-domain acoustic signal to simulate the underwater acoustic signals received by underwater gliders at different underwater positions from the same radiation noise source.

[0044] Optionally, it further includes: a multi-modal visual scene fusion module, and the multi-modal visual scene fusion module includes a three-dimensional point cloud reconstruction device, a motion trajectory compensator, and a head-mounted display terminal;

[0045] The three-dimensional point cloud reconstruction device is used to scan the motion trajectory point cloud data of the underwater glider in the simulation experiment, and generate preliminary three-dimensional data of the underwater glider's motion based on the scanning results;

[0046] The motion trajectory compensator is used to fuse the sensor data in the dynamic motion simulation turntable with the preliminary three-dimensional data through the set Kalman filter to generate a three-dimensional motion trajectory with attitude compensation;

[0047] The head-mounted display terminal is connected to the motion trajectory compensator and is used to display the three-dimensional motion trajectory of the underwater glider to the user or switch to the multi-view observation mode. The multi-view observation mode supports the overlay display of the acoustic heat map and the interactive correction of kinematic parameters.

[0048] In a second aspect, an embodiment of the present invention provides a hardware-in-the-loop simulation method for underwater target detection. The method is applied to the above-mentioned hardware-in-the-loop simulation system for underwater target detection, and the method includes:

[0049] Obtain the kinematic parameters of the underwater glider and the radiation noise source of the underwater target;

[0050] Use the motion attitude simulation module of the simulation controller to solve the kinematic parameters, generate a pose control command with a timestamp and transmit it to the dynamic motion simulation turntable, so that the dynamic motion simulation turntable drives the underwater glider to simulate the underwater motion attitude;

[0051] Call the underwater acoustic signal simulation module of the simulation controller to solve the radiation noise source and generate virtual underwater acoustic data with multi-target azimuth characteristics;

[0052] According to the underwater acoustic characteristic information of the virtual underwater acoustic data, use the multi-band underwater acoustic signal simulator to convert the virtual underwater acoustic data into a time-domain acoustic signal and transmit it to the underwater glider to simulate the underwater detection target of the underwater glider.

[0053] (III) Advantageous Effects

[0054] The beneficial effects of the present invention are as follows: The present invention constructs a hardware-in-the-loop simulation system for the underwater motion attitude of the underwater glider through the simulation controller and the dynamic motion simulation turntable, and at the same time constructs a hardware-in-the-loop simulation system for the underwater target detection of the underwater glider through the simulation controller and the multi-band underwater acoustic signal simulator. Compared with the prior art, the present invention constructs a double-test and verification hardware-in-the-loop simulation system, which can complete the target detection ability test of the underwater glider in any motion attitude, thereby greatly improving the test and verification efficiency of the underwater glider and reducing the cost investment.

[0055] Meanwhile, the simulation controller and multi-band underwater acoustic signal simulator proposed by the present invention simulate underwater acoustic data with multi-target azimuth characteristics through simulation to reproduce the target detection and inspection of the underwater glider in various underwater environments, improving the comprehensiveness of the test and inspection of the underwater glider, and further improving the accuracy and reliability of the test and inspection. Description of the Drawings

[0056] Figure 1 It is a schematic structural diagram of a hardware-in-the-loop simulation system for underwater target detection provided by an embodiment of the present invention;

[0057] Figure 2 It is a transmission flow chart of an analog underwater acoustic signal with a frequency above 10KHz provided by an embodiment of the present invention;

[0058] Figure 3 It is an actual motion trajectory diagram of an underwater glider provided by an embodiment of the present invention.

[0059] Figure 4 It is a position planning diagram during the diving process of a simulated underwater glider provided by an embodiment of the present invention;

[0060] Figure 5 It is a position planning diagram during the surfacing process of a simulated underwater glider provided by an embodiment of the present invention;

[0061] Figure 6 It is a schematic flow chart of a hardware-in-the-loop simulation method for underwater target detection provided by an embodiment of the present invention. Detailed Embodiments

[0062] To better explain the present invention for easy understanding, the present invention will be described in detail below with reference to the accompanying drawings and through specific embodiments.

[0063] Refer to Figure 1 As shown, a hardware-in-the-loop simulation system for underwater target detection proposed by an embodiment of the present invention is applied to construct a hardware-in-the-loop simulation test environment for an underwater glider, and it includes: a dynamic motion simulation turntable for driving the underwater glider to simulate an underwater motion posture; a multi-band underwater acoustic signal simulator for performing underwater acoustic characteristic analysis and synchronous DAC conversion on the input virtual underwater acoustic data with multi-target azimuth characteristics, obtaining time-domain acoustic signals of at least two frequencies, and transmitting the time-domain acoustic signals of all frequencies to the underwater glider through a preset underwater acoustic signal coupling array; a simulation controller for using the configured first calculation channel to solve the kinematic parameters of the underwater glider, generating a pose control command with a timestamp and transmitting it to the dynamic motion simulation turntable; and using the configured second calculation channel to solve the radiation noise source of the preset underwater target, generating virtual underwater acoustic data with multi-target azimuth characteristics and transmitting it to the multi-band underwater acoustic signal simulator.

[0064] In this embodiment, a hardware-in-the-loop simulation system for the underwater motion attitude of an underwater glider is constructed by a simulation controller and a dynamic motion simulation turntable. At the same time, a hardware-in-the-loop simulation system for the underwater target detection of an underwater glider is also constructed by the simulation controller and a multi-band underwater acoustic signal simulator. Compared with the prior art, by constructing a dual-test hardware-in-the-loop simulation system in this embodiment, it can complete the target detection ability test of the underwater glider in any motion attitude, thereby greatly improving the test and inspection efficiency of the underwater glider and reducing the cost investment.

[0065] At the same time, the simulation controller and the multi-band underwater acoustic signal simulator proposed in this embodiment simulate underwater acoustic data with multi-target azimuth characteristics through simulation to reproduce the target detection and inspection of the underwater glider in various underwater environments, improving the comprehensiveness of the test and inspection of the underwater glider, and further improving the accuracy and credibility of the test and inspection.

[0066] To better understand the above technical solution, the exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more clear and thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0067] First, the dynamic motion simulation turntable includes: a turntable platform, a multi-degree-of-freedom dynamic drive mechanism, and a multi-modal sensor array.

[0068] The turntable platform is used to carry the underwater glider. The turntable platform is provided with a fixing mechanism, and the fixing mechanism fixes the underwater glider on the turntable platform. Any model of underwater glider can be fixed on the turntable platform through the fixing mechanism, so that the underwater glider on the turntable platform can move synchronously with the rotation of the turntable platform.

[0069] The multi-degree-of-freedom dynamic drive mechanism includes: a drive motor and a transmission device. The transmission device is respectively connected to the drive motor and the turntable platform. The transmission device is used to drive the turntable platform to perform a three-degree-of-freedom motion including acceleration change and angular velocity change under the power provided by the drive motor. The drive motor usually adopts a DC motor or an AC motor, and the motion of the turntable is realized by controlling the start-stop, speed and steering of the motor.

[0070] The multi-modal sensor array includes: an accelerometer, a resolver, and a multi-axis inclinometer, which constitute a closed-loop detection network for the motion state, and can collect in real time the motion state information of the turntable platform, including the pitch angle error compensation amount, the angular velocity compensation parameter, and the acceleration dynamic response characteristic. These motion state information can be used to correct the motion data error between the pose control instruction output by the simulation controller and the actual operation action executed by the turntable platform.

[0071] Secondly, the multi-band underwater acoustic signal simulator includes: an underwater acoustic characteristic analysis module and an underwater acoustic signal coupling array. The multi-band underwater acoustic signal simulator first uses the underwater acoustic characteristic analysis module to perform underwater acoustic characteristic analysis processing and synchronous DAC (Digital-to-Analog Converter) conversion on the virtual underwater acoustic data of the multi-target azimuth characteristics to obtain time-domain acoustic signals of at least two frequencies (the propeller noise, engine vibration noise, and auxiliary engine vibration noise in the same device are not at the same frequency), and then transmits the time-domain acoustic signals of all frequencies to the underwater glider through the underwater acoustic signal coupling array to achieve the effect of simulating underwater targets.

[0072] Furthermore, the underwater acoustic characteristic analysis module is used to perform underwater acoustic characteristic analysis processing and synchronous DAC conversion on the input virtual underwater acoustic data of the multi-target azimuth characteristics through the deployed underwater target acoustic characteristic model to obtain time-domain acoustic signals of at least two frequencies. Among them, the mathematical expression of the underwater acoustic signal target acoustic characteristic model is:

[0073]

[0074] In formula (1), H(t) represents the output quantity of the time-domain acoustic signal, n represents the number of underwater targets, β i represents the azimuth parameter of the i-th underwater target, τ i represents the time-delay parameter of the i-th underwater target, S(t) represents the underwater target radiation noise source, λ i represents the angular frequency of the i-th underwater target, Smac(t) represents the mechanical noise line spectrum, Sprop(t) represents the propeller blade line spectrum, Smodu(t) represents the propeller modulation spectrum, and Sconti(t) represents the continuous noise spectrum.

[0075] Furthermore, the underwater acoustic signal coupling array is used to transmit the time-domain acoustic signals of all frequencies to the underwater glider through the configured dual acoustic coupling channels. The dual acoustic coupling channels include: a transducer array and an optical fiber transmission component. The transducer array is connected to the underwater acoustic characteristic analysis module to form the first acoustic coupling channel, so as to convert the time-domain acoustic signals with frequencies above 10KHz into spatial acoustic signals, and transmit the spatial acoustic signals to the receiving hydrophone of the underwater glider through a preset propagation medium; the optical fiber transmission component is respectively connected to the underwater acoustic characteristic analysis module and the underwater glider to form the second acoustic coupling channel, so as to transmit the time-domain acoustic signals with frequencies below 10KHz to the target detection signal acquisition end of the underwater glider through the "electric-optical-electric" transmission mode, so that the target information carried by the time-domain acoustic signals in this frequency band directly acts on the target detection and processing system of the underwater glider. The dual acoustic coupling channels of the underwater acoustic signal coupling array can simulate the transmission of time-domain acoustic signals of any frequency acting on the underwater glider, so that the deployed simulation experiments can simulate any underwater target to conduct detection tests on the underwater glider.

[0076] To further explain, the transducer array includes: a conditioning circuit and transducer array elements. The conditioning circuit is used to perform signal conditioning including signal power amplification and impedance matching on the time-domain acoustic signals with frequencies above 10KHz to obtain time-domain acoustic signals impedance-matched to the preset propagation medium. The transducer array elements are connected to the conditioning circuit and are used to generate and output spatial acoustic signals to the propagation medium after docking with the receiving hydrophone through the propagation medium, so that the spatial acoustic signals are transmitted to the receiving hydrophone through the propagation medium.

[0077] In this embodiment, referring to Figure 2 As shown, after receiving the virtual underwater acoustic data generated by the simulation controller solving the radiation noise source of the underwater target, the multi-band underwater acoustic signal simulator uses the DAC to synchronously convert the virtual underwater acoustic data into multiple time-domain acoustic signals of different frequencies; then, uses the conditioning circuit to condition each time-domain acoustic signal (mainly including signal power amplification and impedance matching); then, outputs the conditioned time-domain acoustic signals to the corresponding transducer array elements, and the transducer array elements generate corresponding spatial acoustic signals; finally, transmits the spatial acoustic signals to the receiving hydrophone of the underwater glider through the coupling propagation medium. Among them, matching the impedance of the time-domain acoustic signal with that of the propagation medium ensures that the spatial acoustic signal emitted by the transducer array elements can be transmitted to the receiving hydrophone of the underwater glider with high efficiency and without distortion.

[0078] Next, the simulation controller includes: a motion attitude simulation module and an underwater acoustic signal simulation module. The motion attitude simulation module is used to solve the kinematic parameters of the underwater glider through the underwater glider kinematic model in the configured first calculation channel, generate pose control instructions with timestamps, and transmit them to the dynamic motion simulation turntable. The underwater acoustic signal simulation module is used to solve the radiation noise source of the preset underwater target through the configured second calculation channel, generate virtual underwater acoustic data with multi-target azimuth characteristics, and transmit them to the multi-band underwater acoustic signal simulator. Among them, the mathematical expression of the underwater glider kinematic model is:

[0079]

[0080] In Equation (2), α represents the angular acceleration of the underwater glider, ω represents the angular velocity of the underwater glider, R represents the equipment change constant of the underwater glider, m represents the mass of the moving mass block of the underwater glider, g represents the acceleration due to gravity, x represents the lateral position of the underwater glider, z represents the depth of the underwater glider, θ represents the pitch angle of the underwater glider, x(t) represents the lateral displacement of the underwater glider, z(t) represents the depth displacement of the underwater glider, ξ represents the time constant, u x represents the lateral control input of the underwater glider, u z represents the depth control input of the underwater glider, T y represents the inertial matrix component in the longitudinal direction of the underwater glider.

[0081] In this embodiment, referring to Figure 3 as shown, the motion trajectory of the underwater glider during actual gliding is basically a "V"-shaped zigzag motion trajectory in the longitudinal vertical plane. Therefore, the motion constraint of the underwater glider is mainly in the longitudinal vertical plane, that is, the lateral control input and the lateral control input of the underwater glider, and based on this, the underwater glider kinematic model shown in Equation (2) is established, which reduces the model calculation complexity and improves the solution efficiency without affecting the model solution accuracy.

[0082] In this embodiment, the underwater glider kinematic model is encapsulated in the FMU format. The underwater glider kinematic model in the FMU format includes: a model description file, a model code file, and a binary dynamic library. The model description file is used to store the metadata and information of the underwater glider kinematic model to describe the structure, parameters, and input and output variables of the underwater glider kinematic model. The model code file is used to store the code of the underwater glider kinematic model algorithm. The binary dynamic library is used to compile the model code file in binary format.

[0083] Finally, a hardware-in-the-loop simulation system for underwater target detection proposed in this embodiment further includes: a multi-modal visual scene fusion module, and the multi-modal visual scene fusion module includes a three-dimensional point cloud reconstruction device, a motion trajectory compensator, and a head-mounted display terminal.

[0084] The three-dimensional point cloud reconstruction device is used to scan the motion trajectory point cloud data of the underwater glider in the simulation experiment, and generate the preliminary three-dimensional data of the underwater glider's motion based on the scanning results.

[0085] The motion trajectory compensator is used to fuse the sensor data in the dynamic motion simulation turntable with the preliminary three-dimensional data through the set Kalman filter to generate a three-dimensional motion trajectory with attitude compensation. The sensor data is mainly provided by the multi-modal sensor array in the dynamic motion simulation turntable.

[0086] The head-mounted display terminal is connected to the motion trajectory compensator and is used to display the three-dimensional motion trajectory of the underwater glider to the user or switch to the multi-view observation mode. The multi-view observation mode supports the overlay display of the acoustic heat map and the interactive correction of kinematic parameters.

[0087] It is worth mentioning that when the hardware-in-the-loop simulation system for underwater target detection proposed by this embodiment conducts a simulation experiment on the underwater glider for target detection, the number of underwater gliders for the simulation experiment is configured to be at least three, and a time delay device is provided at the target detection signal acquisition end of each underwater glider. The time delay device is used to perform time delay processing on the time-domain acoustic signal in the same frequency band to simulate the underwater acoustic signals received by the underwater gliders at different underwater positions from the same radiated noise source, as Figure 4 and Figure 5 shown.

[0088] In addition, as shown in Figure 6 this embodiment also proposes a hardware-in-the-loop simulation method for underwater target detection. This method is applied to the hardware-in-the-loop simulation system for underwater target detection described above, and it includes:

[0089] S100. Obtain the kinematic parameters of the underwater glider and the radiated noise source of the underwater target.

[0090] S200. Use the motion attitude simulation module of the simulation controller to solve the kinematic parameters, generate a pose control command with a timestamp and transmit it to the dynamic motion simulation turntable, so that the dynamic motion simulation turntable drives the underwater glider to simulate the underwater motion attitude.

[0091] S300. Use the underwater acoustic signal simulation module of the simulation controller to solve the radiated noise source and generate virtual underwater acoustic data with multi-target azimuth characteristics.

[0092] S400. According to the underwater acoustic characteristics information of the virtual underwater acoustic data, use the multi-band underwater acoustic signal simulator to convert the virtual underwater acoustic data into a time-domain acoustic signal and transmit it to the underwater glider to simulate the underwater target detection of the underwater glider.

[0093] In summary, the embodiments of the present invention propose a hardware-in-the-loop simulation system and method for underwater target detection, which can realize the synchronous simulation experiments in two aspects of the underwater motion attitude of the underwater glider and underwater target detection, that is, while simulating the underwater motion attitude of the underwater glider, the underwater target detection function of the underwater glider is simulated experimentally, and then the detection ability test of the underwater glider under any motion attitude can be simulated, meeting the inspection requirements for the comprehensive performance of the underwater glider, improving the test and inspection efficiency of the underwater glider and reducing the cost investment.

[0094] At the same time, the multi-band underwater acoustic signal simulator reproduces the target detection inspection of the underwater glider in various underwater environments by simulating underwater acoustic data with multi-target azimuth characteristics, further improving the comprehensiveness of the test and inspection of the underwater glider; and through the set dual acoustic coupling channels, underwater acoustic signals of any frequency can also be applied to the underwater glider, further improving the accuracy of the inspection of the underwater target detection function of the underwater glider.

[0095] Since the system / device described in the above embodiments of the present invention is the system / device adopted for implementing the method in the above embodiments of the present invention, based on the method described in the above embodiments of the present invention, those skilled in the art can understand the specific structure and deformation of the system / device, and thus will not be described in detail here. Any system / device adopted by the method in the above embodiments of the present invention belongs to the scope of protection of the present invention.

[0096] Those skilled in the art should understand that the embodiments of the present invention can be provided as a method, a system, or a computer program product. Therefore, the present invention can be implemented in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present invention can be implemented in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0097] The present invention is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present invention. It should be understood that each flow and / or block in the flowcharts and / or block diagrams can be implemented by computer program instructions, and the combination of flows and / or blocks in the flowcharts and / or block diagrams can also be implemented.

[0098] It should be noted that in the description of the present invention, the words "a" or "an" preceding a component do not exclude the existence of multiple such components. The present invention can be implemented by means of hardware including several different components and by means of a properly programmed computer. The use of the words first, second, third, etc. is only for the convenience of expression and does not represent any order. These words can be understood as part of the component name.

[0099] In addition, it should be noted that in the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0100] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments after learning the basic creative concepts.

[0101] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention.

Claims

1. A semi-physical simulation system for underwater target detection, characterized in that: The system is used to construct a semi-physical simulation test environment for an underwater glider, and the system includes: Dynamic motion simulation turntable, used to drive the underwater glider to simulate underwater motion posture; A multi-band hydroacoustic signal simulator is used to perform hydroacoustic characteristic analysis and synchronous DAC conversion on the input virtual hydroacoustic data of multi-target azimuth characteristics, obtain time-domain acoustic signals of at least two frequencies, and transmit the time-domain acoustic signals of all frequencies to the underwater glider through a preset hydroacoustic signal coupling array; The simulation controller is used to use the configured first computing channel to solve the kinematic parameters of the underwater glider, generate a posture control instruction with a timestamp and transmit it to the dynamic motion simulation turntable; and use the configured second computing channel to solve the radiation noise source of the preset underwater target, generate virtual hydroacoustic data of multi-target azimuth characteristics and transmit it to the multi-band hydroacoustic signal simulator.

2. A semi-physical simulation system for underwater target detection as claimed in claim 1, characterized in that: Dynamic Motion Simulation Turntable includes: A turntable platform for carrying underwater gliders; The turntable platform is provided with a fixing mechanism, which is used to fix the underwater glider on the turntable platform; A multi-degree-of-freedom dynamic drive mechanism includes a drive motor and a transmission device, wherein the transmission device is respectively connected to the drive motor and the turntable platform, and the transmission device is used to drive the turntable platform to perform a three-degree-of-freedom motion including acceleration change and angular velocity change under the power provided by the drive motor; The multimodal sensor array, including accelerometers, rotary transformers and multi-axis inclination sensors, constitutes a closed-loop motion state detection network to collect the motion state information of the turntable platform including pitch angle error compensation, angular velocity compensation parameters and acceleration dynamic response characteristics in real time.

3. A semi-physical simulation system for underwater target detection as claimed in claim 1, characterized in that: The multi-band hydroacoustic signal simulator includes: An underwater acoustic characteristic analysis module is used to perform underwater acoustic characteristic analysis and synchronous DAC conversion on the input virtual underwater acoustic data of multi-target azimuth characteristics through a preset underwater target acoustic characteristic model to obtain time domain acoustic signals of at least two frequencies; An underwater acoustic signal coupling array is used to transmit time-domain acoustic signals of all frequencies to the underwater glider through configured dual acoustic coupling channels; Among them, the mathematical expression of the acoustic characteristic model of the underwater acoustic signal target is: In the formula, H(t) represents the output of the acoustic signal in the time domain, n represents the number of underwater targets, and β i represents the orientation parameter of the i-th underwater target, τ i represents the time delay parameter of the ith underwater target, S(t) represents the noise source radiated by the underwater target, and λ i represents the angular frequency of the i underwater targets, Smac(t) represents the mechanical noise line spectrum, Sprop(t) represents the propeller blade line spectrum, Smodu(t) represents the propeller modulation spectrum, and Sconti(t) represents the continuous noise spectrum.

4. A semi-physical simulation system for underwater target detection as claimed in claim 3, characterized in that: Dual acoustic coupling channels include: The transducer array is connected to the underwater acoustic characteristic analysis module, and is used to convert the time domain acoustic signal with a frequency above 10KHz into a spatial acoustic signal, and transmit the spatial acoustic signal to the receiving hydrophone of the underwater glider through a preset propagation medium; The optical fiber transmission component is connected to the hydroacoustic characteristic analysis module and the underwater glider respectively, and is used to transmit the time domain acoustic signal with a frequency below 10KHz to the target detection signal acquisition end of the underwater glider.

5. A semi-physical simulation system for underwater target detection as claimed in claim 4, characterized in that: The transducer array includes: A conditioning circuit, used for performing signal conditioning including signal power amplification and impedance matching on a time-domain acoustic signal with a frequency above 10 KHz, to obtain a time-domain acoustic signal that matches a preset propagation medium impedance; The transducer array element is connected to the conditioning circuit and is used to generate a spatial acoustic signal and output it to the propagation medium after docking with the receiving hydrophone through the propagation medium, so that the spatial acoustic signal is transmitted to the receiving hydrophone through the propagation medium.

6. A semi-physical simulation system for underwater target detection as claimed in claim 1, characterized in that: The simulation controller includes: A motion attitude simulation module, used for solving the kinematic parameters of the underwater glider through the underwater glider kinematic model in the configured first calculation channel, generating a posture control instruction with a timestamp and transmitting it to the dynamic motion simulation turntable; An underwater acoustic signal simulation module is used to solve the radiation noise source of the preset underwater target through the configured second calculation channel, generate virtual underwater acoustic data of multi-target azimuth characteristics and transmit it to a multi-band underwater acoustic signal simulator; Among them, the mathematical expression of the underwater glider kinematic model is: Where α represents the angular acceleration of the underwater glider, ω represents the angular velocity of the underwater glider, R represents the equipment change constant of the underwater glider, m represents the mass of the mobile mass block of the underwater glider, g represents the gravitational acceleration, x represents the lateral position of the underwater glider, z represents the depth of the underwater glider, θ represents the pitch angle of the underwater glider, x(t) represents the lateral displacement of the underwater glider, z(t) represents the depth displacement of the underwater glider, ξ represents the time constant, and u x represents the lateral control input of the underwater glider, u z represents the depth control input of the underwater glider, T y Represents the inertia matrix component in the longitudinal direction of the underwater glider.

7. A semi-physical simulation system for underwater target detection as claimed in claim 6, characterized in that: The underwater glider kinematic model is packaged in FMU format. The underwater glider kinematic model in FMU format includes: Model description file, used to store metadata and information of the underwater glider kinematic model to describe the structure, parameters, and input and output variables of the underwater glider kinematic model; Model code file, used to store the code of underwater glider kinematic model algorithm; Binary dynamic library, used to compile model code files in binary format.

8. A semi-physical simulation system for underwater target detection as claimed in claim 1, characterized in that: The number of underwater gliders is configured to be at least three, and a target detection signal collection end of each underwater glider is provided with a delay device; The delay device is used to delay the same time domain acoustic signal to simulate the underwater glider receiving the underwater acoustic signal of the same radiated noise source at different underwater locations.

9. A semi-physical simulation system for underwater target detection as claimed in claim 1, characterized in that: Also includes: A multimodal visual fusion module, which includes a three-dimensional point cloud reconstruction device, a motion trajectory compensator, and a head-mounted display terminal; The three-dimensional point cloud reconstruction device is used to scan the point cloud data of the motion trajectory of the underwater glider in the simulation experiment, and generate preliminary three-dimensional data of the underwater glider's motion based on the scanning results; The motion trajectory compensator is used to fuse the sensor data in the dynamic motion simulation turntable with the preliminary three-dimensional data through the set Kalman filter to generate a three-dimensional motion trajectory with attitude compensation; The head-mounted display terminal is connected to the motion trajectory compensator to display the three-dimensional motion trajectory of the underwater glider to the user or switch to the multi-view observation mode. The multi-view observation mode supports the overlay display of acoustic thermal maps and interactive correction of kinematic parameters.

10. A semi-physical simulation method for underwater target detection, characterized in that: The method is applied to a semi-physical simulation system for underwater target detection as described in any one of claims 1 to 9, and the method comprises: Obtain the kinematic parameters of the underwater glider and the radiated noise source of the underwater target; The motion attitude simulation module of the simulation controller is used to solve the kinematic parameters, generate the attitude control instructions with time stamps and transmit them to the dynamic motion simulation turntable, so that the dynamic motion simulation turntable drives the underwater glider to simulate the underwater motion attitude; The underwater acoustic signal simulation module of the simulation controller is called to solve the radiation noise source and generate virtual underwater acoustic data with multi-target azimuth characteristics; According to the hydroacoustic characteristic information of the virtual hydroacoustic data, a multi-band hydroacoustic signal simulator is used to convert the virtual hydroacoustic data into time-domain acoustic signals and transmit them to the underwater glider to simulate the underwater detection target of the underwater glider.

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