Towed towed buoy array positioning device and positioning method

Abstract

The invention relates to a towed towed buoy array positioning device and method. The towed towed buoy array positioning device comprises a towed mother ship, and a deck unit is fixedly installed on the towed mother ship; the system further comprises a plurality of dragging buoys which are connected in series through ropes and form a dragging buoy array, the dragging buoy located at the foremost end is connected with the dragging mother ship through the rope, and the whole dragging buoy array is dragged by the dragging mother ship on the water surface to sail. The dragging buoy located at the tail end is arranged in a transverse offset mode, complex installation and calibration are not needed before use, and laying and recycling are convenient; the acoustic measurement sensor is always kept far away from a mother ship and is less interfered by ship body noise, so that the acoustic positioning calculation precision is greatly improved; according to the device, accurate positioning of deep towing is achieved based on the spatial distance intersection positioning principle, the base line of the acoustic measurement sensor array is long, the accuracy advantage of long base line positioning is achieved, no positioning tracking ship is arranged in the method, and compared with a double-ship positioning method, the manpower and material resource cost is reduced through the method.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater precise positioning devices, and in particular to a towed buoy array positioning device and a positioning method. Background Art

[0002] As a carrier of underwater detection equipment, the deep-sea towed detection system has currently become an important tool for ocean scientific research and marine geological exploration. The deep-sea towed detection system mainly consists of a towed mother ship, a deck winch, a tow cable, a deep-sea towed body (hereinafter referred to as deep tow), etc. The precise positioning of the deep tow is an important guarantee for it to complete the detection operation task.

[0003] The deep tow is generally positioned underwater by an on-board ultra-short baseline device, and there are two working modes: single-ship operation and double-ship operation. In the single-ship operation mode, the ultra-short baseline device is installed on the towed mother ship, and the general ratio of the depth of the deep tow to the length of the tow cable is 1:3. At this time, the acoustic incidence angle is too large and the acoustic ray bending is relatively serious. The positioning accuracy of the ultra-short baseline is usually low, and it can even only be used to determine the azimuth of the deep tow, and cannot precisely position the deep tow (see the paper "Discussion on the Technical Advantages of Double-Ship Positioning in Deep-Tow Operations", Xiao Jiayao, 2014). In the double-ship operation mode, the ultra-short baseline device is installed on the positioning and tracking ship. The positioning and tracking ship follows the towed mother ship and sails, and by controlling the spacing, it always keeps directly above the deep tow, which makes the opening angle of the ultra-short baseline beam remain within a very small range, greatly improving the positioning accuracy of the deep tow. The paper "Application Status and Optimization Design of the DT-1 Deep-Tow System" (Liu Qi, China Equipment Engineering, 2018) proposes that the double-ship operation mode should be adopted when conducting deep-tow surveys at a working water depth exceeding 1000m. However, there are the following two deficiencies in using the on-board ultra-short baseline device to position the deep tow: 1) The ultra-short baseline device needs to be precisely calibrated for the installation position and installation angle before use. The mother ship needs to collect a large amount of data according to the planned track and complete the calibration before use, and it cannot be used immediately after installation; 2) The ultra-short baseline device is installed on the ship and is easily affected by the hull noise. The lower signal-to-noise ratio will reduce the positioning accuracy of the device, and in severe cases, the positioning calculation cannot even be performed.

[0004] In summary, using the on-board ultra-short baseline device to position the deep tow has certain defects, mainly manifested in two aspects: low positioning accuracy and cumbersome installation and calibration. Although the double-ship operation mode can greatly improve the positioning accuracy, it also increases a lot of human and material costs. Summary of the Invention

[0005] In view of the above-mentioned drawbacks in the existing production technology, the present applicant provides a towed towed buoy array positioning device and a positioning method, so as to tow the mother ship, which has the following main advantages: 1) No complex installation and calibration are required before use, and the deployment and recovery are relatively convenient; 2) The acoustic measurement sensor always maintains a relatively long distance from the mother ship, and is less affected by the hull noise, greatly improving the accuracy of acoustic positioning calculation; 3) The device realizes precise positioning of deep tow based on the principle of spatial distance intersection positioning. The baseline of the acoustic measurement sensor array is relatively long, having the accuracy advantage of long baseline positioning; 4) This method no longer requires a positioning and tracking ship. Compared with the dual-ship positioning method, this method reduces the labor and material costs.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A towed towed buoy array positioning device includes a towed mother ship, and a deck unit is fixedly installed on the towed mother ship; it also includes a plurality of towed buoys connected in series by ropes to form a towed buoy array. The towed buoy at the front end is connected to the towed mother ship by a rope, and the entire towed buoy array is towed and navigated on the water surface by the towed mother ship; the towed buoy at the end is laterally offset.

[0008] Its further technical solution lies in:

[0009] A towed buoy array is composed of at least three towed buoys.

[0010] A towed buoy array is composed of three towed buoys connected in series.

[0011] The three towed buoys are in a triangular shape.

[0012] The control method for the lateral offset of the towed buoy at the end adopts a manual adjustment mode and an automatic adjustment mode.

[0013] The structure of a single towed buoy is as follows: it includes a main body frame, a buoyancy block, a tow ring, a ballast iron, a steering rudder, a hydrophone, a satellite positioning antenna, a deck 5G antenna, a watertight electronic cabin, and a winch. A buoyancy block is arranged above the main body frame, a tow ring is arranged outside one end of the main body frame, a winch is arranged outside the other end of the main body frame, and the winch is connected to a rope. A satellite positioning antenna and a deck 5G antenna are arranged on the top surface of the main body frame. A ballast iron is fixed to the bottom surface of the main body frame, a hydrophone is arranged at the bottom of the ballast iron, and a watertight electronic cabin is arranged inside the main body frame. A bow steering rudder and a stern steering rudder are arranged in front and behind the watertight electronic cabin respectively.

[0014] Inside the watertight electronic cabin, there are distributed a battery, a power module, a clock module, a control module, a 5G module, a satellite positioning module, and an acoustic ranging module.

[0015] The deck unit includes a 5G antenna and a control box. The 5G antenna is used to receive the original measurement data, clock information, satellite positioning information, acoustic ranging information, and steering rudder status information from the towed buoy, and simultaneously transmit control instructions to the towed buoy. The control box includes a main control board, an acoustic positioning calculation module, a 5G module, and a power module.

[0016] A positioning method for a towed towed buoy array positioning device. The positioning method combines the formation control principle and the spatial distance intersection positioning principle, and includes the following operation process:

[0017] Formation control:

[0018] The spatial distance intersection positioning method is used to calculate the deep tow position. To ensure a unique solution for the spatial distance intersection positioning method, the towed buoy array needs to be a planar array and cannot be a linear array.

[0019] For the lateral offset control of the end towed buoy, in the automatic adjustment mode, first, a minimum lateral offset value and a maximum lateral offset value are set. Then, based on the satellite positioning results of each towed buoy, the current lateral offset of the end towed buoy is calculated. Subsequently, the main control board of the deck unit generates control instructions according to the feedback control algorithm. One is sent to the control module of the end towed buoy to make it adjust the bow steering rudder to generate a certain rudder angle, driving the end towed buoy to rotate and laterally offset. The other is sent to the control modules of the intermediate towed buoys to make them adjust the stern steering rudder to generate a certain rudder angle, suppressing the rotation and lateral offset of the intermediate towed buoys. Finally, under the combined action of the rope tension and water flow resistance, the end towed buoy rotates and laterally offsets, and the towed buoy array presents a triangular planar array. In the manual adjustment mode, the operator manually inputs control instructions to the main control board of the deck unit according to the position relationship of each towed buoy, and then transmits them to the end towed buoy and the intermediate towed buoys, finally driving their own steering rudders to make the end towed buoy rotate and laterally offset, and the towed buoy array presents a triangular planar array form.

[0020] Positioning calculation:

[0021] In terms of acoustic ranging, it is necessary to unify the time reference with the deep tow. After the deep tow enters the water and reaches the specified operation depth, it needs to periodically transmit acoustic signals with timestamp information for the towed buoy to receive and process. The hydrophone transmits the measured acoustic signals to the acoustic ranging module in real time. The acoustic ranging module calculates the transmission time information of the acoustic signals and combines the current time information of the clock module, and uses this time difference to calculate the distance parameter information between the deep tow and the towed buoy.

[0022] In terms of deep-tow position calculation, based on the principle of intersection positioning by spatial distance, on the one hand, each towed buoy measures the distance parameter information between the deep-tow and itself through acoustic ranging means, and transmits this information, together with the original measurement data of the towed buoy hydrophone and the clock information, to the acoustic positioning calculation module of the deck unit in real time. On the other hand, each towed buoy obtains its own position information through satellite positioning means and transmits this position information to the acoustic positioning calculation module of the deck unit in real time. Finally, the acoustic positioning calculation module of the deck unit uses the robust least squares method to calculate the position information of the underwater target in real time according to the data information received from the above two aspects. In some working conditions with higher accuracy requirements, the original measurement data of the towed buoy hydrophone and the clock information can be further fused for data fusion processing to improve the accuracy of acoustic positioning calculation.

[0023] The beneficial effects of the present invention are as follows:

[0024] (1) Precise positioning: This positioning device is based on the principle of intersection positioning by spatial distance, has the accuracy advantage similar to that of a long baseline positioning system, and can also adjust the distance between the acoustic measurement array and the towed mother ship by changing the length of the connecting rope between the towed buoy and the towed mother ship, enabling this positioning device to be directly above the deep-tow and keeping it in the best working area. This not only weakens the influence of sound ray bending but also reduces the influence of the noise of the towed mother ship's propeller, ultimately achieving precise positioning of the deep-tow.

[0025] (2) Controllable array shape: Under the working condition of towed navigation, the array shape of the towed buoy array can be controlled and adjusted automatically or manually through the main control board of the deck unit. By controlling the steering rudder, the towed buoy array is kept as a planar array, providing a relatively good positioning calculation condition for this positioning device.

[0026] (3) Variable baseline length: This positioning device can change the length of the connecting rope between each towed buoy by controlling the winch to retract and release according to different towed detection working conditions of the deep-tow (selecting a relatively long connecting rope when the depth is large and a relatively short connecting rope when the depth is small), thereby adjusting the baseline length of the acoustic measurement array, which is relatively flexible in use.

[0027] (4) Convenient to use and calibration-free: The deployment and installation of this positioning device are relatively simple compared with ultra-short baseline equipment. After the deployment and installation are completed, there is no need to arrange a sea trial to calibrate the installation deviation of the equipment. Therefore, this positioning device is more convenient to use and can be used immediately after installation.

[0028] (5) The present invention is mainly applied to the field of underwater positioning technology, especially for the precise positioning of deep-sea towed bodies. Description of the Drawings

[0029] Figure 1This is the system composition diagram of the positioning device of the present invention.

[0030] Figure 2 This is the internal structure schematic diagram of a single towed buoy of the present invention.

[0031] Figure 3 This is the composition diagram of the deck unit of the present invention.

[0032] Figure 4 This is the schematic diagram of the towed buoy formation of the present invention. Detailed implementation manners

[0033] The following will describe the detailed implementation manners of the present invention in conjunction with the accompanying drawings.

[0034] As Figures 1-4 shown, the towed towed buoy array positioning device of this embodiment includes a towing mother ship, and a deck unit is fixedly installed on the towing mother ship; it also includes a plurality of towed buoys connected in series by ropes to form a towed buoy array. The towed buoy at the forefront is connected to the towing mother ship by a rope, and the entire towed buoy array is towed and navigated on the water surface by the towing mother ship; the towed buoy at the rearmost end is horizontally offset.

[0035] A towed buoy array is composed of greater than or equal to three towed buoys.

[0036] A towed buoy array is composed of three towed buoys connected in series.

[0037] The three towed buoys present a triangular shape.

[0038] The control method for the horizontal offset of the towed buoy at the rearmost end adopts a manual adjustment mode and an automatic adjustment mode.

[0039] The structure of a single towed buoy is as follows: it includes a main body frame, buoyancy blocks, a towing ring, ballast iron, steering rudders, a hydrophone, a satellite positioning antenna, a deck 5G antenna, a watertight electronic cabin, and a winch. Buoyancy blocks are arranged above the main body frame, a towing ring is arranged outside one end of the main body frame, a winch is arranged outside the other end of the main body frame, the winch is connected to a rope, a satellite positioning antenna and a deck 5G antenna are arranged on the top surface of the main body frame, ballast iron is fixed at the bottom of the main body frame, a hydrophone is arranged at the bottom of the ballast iron, a watertight electronic cabin is arranged inside the main body frame, and a bow steering rudder and a stern steering rudder are arranged in front of and behind the watertight electronic cabin respectively.

[0040] Inside the watertight electronic cabin, there are distributed a battery, a power module, a clock module, a control module, a 5G module, a satellite positioning module, and an acoustic ranging module.

[0041] The deck unit includes a 5G antenna and a control box. The 5G antenna is used to receive the original measurement data of the hydrophone from the towed buoy, clock information, satellite positioning information, acoustic ranging information, and steering rudder status information, and at the same time transmit control instructions to the towed buoy; the control box includes a main control board, an acoustic positioning calculation module, a 5G module, and a power module.

[0042] The positioning method of the towed towed buoy array positioning device in this embodiment integrates the formation control principle and the spatial distance intersection positioning principle, and includes the following operation processes:

[0043] Formation control:

[0044] The spatial distance intersection positioning method is used to calculate the deep tow position. To ensure that the spatial distance intersection positioning method has a unique solution, the towed buoy array needs to be a planar array and cannot be a linear array;

[0045] For the lateral offset control of the end towed buoy, in the automatic adjustment mode, first, set a minimum lateral offset value and a maximum lateral offset value; then, based on the satellite positioning results of each towed buoy, calculate the current lateral offset of the end towed buoy; subsequently, the main control board of the deck unit generates control instructions according to the feedback control algorithm. One is sent to the control module of the end towed buoy to make it adjust the bow steering rudder to generate a certain rudder angle, driving the end towed buoy to rotate and laterally offset. The other is sent to the control module of the middle towed buoy to make it adjust the stern steering rudder to generate a certain rudder angle to inhibit the rotation and lateral offset of the middle towed buoy; finally, under the combined action of the rope tension and water flow resistance, the end towed buoy rotates and laterally offsets, and the towed buoy array presents a triangular planar array; in the manual adjustment mode, the operator manually inputs control instructions to the main control board of the deck unit according to the position relationship of each towed buoy, and then transmits them to the end towed buoy and the middle towed buoy, and finally drives its own steering rudder to make the end towed buoy rotate and laterally offset, and the towed buoy array presents a triangular planar array form;

[0046] Positioning calculation:

[0047] In terms of acoustic ranging, it is necessary to unify the time reference with the deep tow. After the deep tow enters the water and reaches the specified operating depth, it needs to periodically emit acoustic signals with timestamp information for the towed buoy to receive and process. The hydrophone transmits the measured acoustic signals to the acoustic ranging module in real time. The acoustic ranging module calculates the transmission time information of the acoustic signals and combines the current time information of the clock module, and uses this time difference to calculate the distance parameter information between the deep tow and the towed buoy;

[0048] In terms of deep-tow position calculation, based on the principle of intersection positioning by spatial distance, on the one hand, each towed buoy measures the distance parameter information between the deep-tow and itself through acoustic ranging, and transmits this information, the original measurement data of the towed buoy hydrophone, and the clock information to the acoustic positioning calculation module of the deck unit in real time. On the other hand, each towed buoy obtains its own position information through satellite positioning and transmits this position information to the acoustic positioning calculation module of the deck unit in real time. Finally, the acoustic positioning calculation module of the deck unit uses the robust least squares method to calculate the position information of the underwater target in real time based on the data information received from the above two aspects. In some working conditions with higher accuracy requirements, the original measurement data of the towed buoy hydrophone and the clock information can be further fused for data fusion processing to improve the accuracy of acoustic positioning calculation.

[0049] The specific structure and functions of the towed towed buoy array positioning device of the present invention are as follows:

[0050] It mainly includes three towed buoys, a deck unit, and a rope.

[0051] Among them, the three towed buoys are connected in series with connecting ropes to form a towed buoy array.

[0052] The foremost towed buoy is connected to the towing mother ship, and the entire towed buoy array is towed and navigated on the water surface by the towing mother ship. The deck unit is fixedly installed on the towing mother ship.

[0053] The towed buoy mainly consists of a main body frame, buoyancy blocks, a towing ring, ballast iron, a steering rudder, a hydrophone, a satellite positioning antenna, a deck 5G antenna, a watertight electronic cabin, and a winch. The schematic diagram of the composition of the towed buoy is as Figure 2 shown.

[0054] Among them, the main body frame provides an installation and connection interface for each component of the towed buoy.

[0055] Among them, the buoyancy blocks are used to provide buoyancy for the towed buoy.

[0056] Among them, the towing ring is the external connection interface of the towed buoy, used to connect two different towed buoys, or to connect the towed buoy and the mother ship.

[0057] Among them, the ballast iron is used to lower the center of gravity of the towed buoy and enhance its stability.

[0058] Among them, the steering rudder consists of a steering gear, a rudder blade, and a transmission rod. The steering gear receives the control instructions of the control module, generates a turning torque, and drives the rudder blade to rotate through the transmission rod, causing the towed buoy to generate a certain rudder angle and realizing the bow direction deflection under the action of the water flow. There are two steering rudders. Steering rudder 1 is arranged at the bow of the towed buoy, and steering rudder 2 is arranged at the stern of the towed buoy.

[0059] Among them, the hydrophone is used to receive the acoustic signals of external sound sources and transmit the signals to the acoustic ranging module in real time.

[0060] Among them, the satellite positioning antenna is used to receive satellite signals and transmit the signals to the satellite positioning module in real time.

[0061] Among them, the deck 5G antenna is used to transmit the original measurement data of the hydrophone, clock information, satellite positioning information, acoustic ranging information, steering rudder status information, etc. to the deck unit in real time, and at the same time receive the manipulation control information from the deck unit.

[0062] Among them, the watertight electronic cabin is mainly composed of a battery, a power module, a clock module, a control module, a 5G module, a satellite positioning module, an acoustic ranging module, etc. Among them, the battery powers the power module, the power module supplies power to each electrical module of the towed buoy, the clock module provides a high-precision time reference for the towed buoy, the 5G module and the deck 5G antenna jointly realize the short-range high-speed two-way communication between the towed buoy and the deck unit, the satellite positioning module is used to calculate satellite signals and provide position and speed information for the towed buoy and accurately time the clock module, and the acoustic ranging module is used to collect the data information of the hydrophone in real time and calculate the distance information between the sound source and the towed buoy. The control module is used on the one hand to receive external control instructions and forward the instructions to the steering gear to control the rotation of the steering gear; on the other hand, it is used to collect the parameter information of the clock module, satellite positioning module, acoustic ranging module and steering rudder status information, and then through the 5G module, integrate and summarize the collected data information and send it to the deck unit in real time.

[0063] Among them, the winch is used to store the connecting rope and receive the instructions of the control module to realize the retraction and release control of the connecting rope.

[0064] The deck unit is mainly composed of a deck 5G antenna and a control box.

[0065] Among them, the deck 5G antenna is used to receive the original measurement data of the hydrophone from the towed buoy, clock information, satellite positioning information, acoustic ranging information, steering gear status information, etc., and at the same time transmit control instructions to the towed buoy. The control box is mainly composed of a main control board, an acoustic positioning calculation module, a 5G module, and a power module. Among them, the main control board is the external interface of this positioning device. On the one hand, it is used to receive external control instructions or automatically generate control instructions according to the control algorithm, and transmit the instructions to the control module of the towed buoy through 5G wireless communication, and finally realize the control of the steering gear; on the other hand, it is used to transmit the position calculation result of the deep tow to external users in real time. The 5G module and the deck 5G antenna jointly realize the short-distance high-speed two-way communication between the towed buoy and the deck unit. The acoustic positioning calculation module calculates the position parameters of the deep tow in real time according to the acoustic ranging information uploaded by each towed buoy (referring to the original measurement data of the hydrophone and clock information of each towed buoy when necessary) and satellite positioning information, and transmits the calculation result to the main control board in real time. The power module is externally connected to the ship's power supply to realize the power supply and distribution of each module of the deck unit.

[0066] In the actual working process, precise positioning is completed through the following process:

[0067] (1) Formation control principle:

[0068] This positioning device mainly works under the towed navigation condition, and uses the spatial distance intersection positioning method to calculate the position of the deep tow. To ensure that the spatial distance intersection positioning method has a unique solution, the towed buoy array needs to be a planar array and cannot be a linear array (directly towed without taking any control measures, and the array result is usually a linear array). Therefore, the present invention proposes to perform lateral offset control on the end towed buoy so as to present a towed buoy array in a triangular shape. The schematic diagram of the towed buoy formation is as Figure 4 shown.

[0069] In terms of the lateral offset control of the end towed buoy, there are mainly two control modes: manual adjustment mode and automatic adjustment mode.

[0070] In the automatic adjustment mode, first, a minimum lateral offset and a maximum lateral offset are set. Then, based on the satellite positioning results of each towed buoy, the current lateral offset of the end towed buoy is calculated. Subsequently, the main control board of the deck unit generates control instructions according to the feedback control algorithm. One is sent to the control module of the end towed buoy to adjust the bow steering rudder to generate a certain rudder angle, driving the end towed buoy to rotate and laterally offset. The other is sent to the control module of towed buoy 2 to adjust the stern steering rudder to generate a certain rudder angle, inhibiting the rotation and lateral offset of towed buoy 2. Finally, under the combined action of the rope tension and water flow resistance, the end towed buoy rotates and laterally offsets, and the towed buoy array presents a triangular planar array. Among them, the basic idea of the feedback control is as follows: If the current lateral offset parameter is within the allowable range of the lateral offset, no adjustment is made. If the parameter is less than the minimum lateral offset, a steering gear control instruction is issued to generate a small rudder angle, causing the end towed buoy to rotate, and then the lateral offset gradually increases. If the parameter is greater than the maximum lateral offset, a steering gear control instruction is issued to zero the rudder angle, and the end towed buoy will gradually reduce the lateral offset under the combined action of the rope tension and water flow resistance.

[0071] In the manual adjustment mode, the operator manually inputs control instructions to the main control board of the deck unit according to the positional relationship of each towed buoy, and then transmits them to the end towed buoy and towed buoy 2, finally driving their own steering rudders to cause the end towed buoy to rotate and laterally offset, and the towed buoy array presents a triangular planar array form.

[0072] (2) Positioning and calculation principle:

[0073] In terms of acoustic ranging, first, the present invention needs to unify the time reference with the deep tow. Second, after the deep tow enters the water, it needs to regularly emit acoustic signals with timestamp information for the towed buoy to receive and process. Then, the hydrophone transmits the measured acoustic signals to the acoustic ranging module in real time. Finally, the acoustic ranging module calculates the distance parameter information between the deep tow and the towed buoy by calculating the emission time information of the acoustic signals and combining the current time information of the clock module, and using this time difference.

[0074] In terms of deep tow position calculation, the present invention is mainly based on the principle of intersection positioning by spatial distance. On the one hand, each towed buoy measures the distance parameter information between the deep tow and itself through acoustic ranging means, and transmits this information, the original measurement data of the towed buoy hydrophone, and the clock information to the acoustic positioning calculation module of the deck unit in real time. On the other hand, each towed buoy obtains its own position information through satellite positioning means and transmits this position information to the acoustic positioning calculation module of the deck unit in real time. Finally, the acoustic positioning calculation module of the deck unit calculates the position information of the underwater target in real time according to the above two aspects of data information received, using the robust least squares method. In some working conditions with higher accuracy requirements, the original measurement data of the towed buoy hydrophone and the clock information can be further fused for data fusion processing to improve the accuracy of acoustic positioning calculation.

[0075] The above description is an explanation of the present invention, not a limitation of the invention. The scope defined by the present invention is referred to the claims. Any form of modification can be made within the protection scope of the present invention.

Claims

1. A towed buoy array positioning device, comprising a towing mother ship, characterized in that: The towing mother ship is fixedly provided with a deck unit; it also includes a plurality of towing buoys connected in series with ropes to form a towing buoy array, the towing buoy at the front end is connected to the towing mother ship by a rope, and the entire towing buoy array is towed by the towing mother ship on the water surface; the towing buoy at the end is laterally offset.

2. A towed buoy array positioning device as claimed in claim 1, characterized in that: A towed buoy array is composed of three or more towed buoys.

3. A towed buoy array positioning device as claimed in claim 1, characterized in that: A towed buoy array is composed of three towed buoys connected in series.

4. A towed buoy array positioning device as claimed in claim 3, characterized in that: The three towed buoys form a triangle shape.

5. A towed buoy array positioning device as claimed in claim 1, characterized in that: The control method for the lateral deviation of the towed buoy at the very end adopts a manual adjustment mode and an automatic adjustment mode.

6. A towed buoy array positioning device as claimed in claim 1, characterized in that: The structure of a single towed buoy is as follows: it includes a main frame, a buoyancy block, a towing ring, a ballast iron, a steering rudder, a hydrophone, a satellite positioning antenna, a deck 5G antenna, a watertight electronic compartment and a winch. A buoyancy block is arranged on the top of the main frame, a towing ring is arranged on the outside of one end of the main frame, a winch is arranged on the outside of the other end of the main frame, the winch is connected by a rope, a satellite positioning antenna and a deck 5G antenna are arranged on the top surface of the main frame, a ballast iron is fixed on the bottom surface of the main frame, a hydrophone is arranged at the bottom of the ballast iron, a watertight electronic compartment is arranged inside the main frame, and a bow steering rudder and a stern steering rudder are arranged in front and behind the watertight electronic compartment respectively.

7. A towed buoy array positioning device as claimed in claim 6, characterized in that: The watertight electronic compartment is equipped with batteries, power modules, clock modules, control modules, 5G modules, satellite positioning modules and acoustic ranging modules.

8. A towed buoy array positioning device as claimed in claim 1, characterized in that: The deck unit includes a 5G antenna and a control box. The 5G antenna is used to receive the original measurement data, clock information, satellite positioning information, acoustic ranging information, and steering rudder status information from the towed buoy, and simultaneously transmit control instructions to the towed buoy; the control box includes a main control board, an acoustic positioning solution module, a 5G module, and a power module.

9. A positioning method for a towed buoy array positioning device as claimed in claim 1, characterized in that: The positioning method combines the formation control principle and the spatial distance intersection positioning principle, including the following operation procedures: Formation Control: The spatial distance intersection positioning method is used to realize deep towing position solution. To ensure that the spatial distance intersection positioning method has a unique solution, the towed buoy array needs to be a surface array, not a line array; In the lateral offset control of the terminal towed buoy, in the automatic adjustment mode, first, a minimum lateral offset and a maximum lateral offset are set; then, the current lateral offset of the terminal towed buoy is solved through the satellite positioning results of each towed buoy; then, the deck unit main control board generates control instructions according to the feedback control algorithm, one of which is sent to the terminal towed buoy control module to adjust the bow steering rudder to produce a certain rudder angle to drive the terminal towed buoy to rotate and deviate laterally; the other is sent to the control module of the middle towed buoy to adjust the stern steering rudder A certain rudder angle is generated to suppress the rotation and lateral deviation of the middle towed buoy; eventually, the end towed buoy rotates and deflects laterally under the combined effect of rope tension and water flow resistance, and the towed buoy array presents a triangular array; in the manual adjustment mode, the operator manually inputs control instructions to the main control panel of the deck unit according to the positional relationship of each towed buoy, and then transmits them to the end towed buoy and the middle towed buoy, and finally drives its own steering rudder to rotate and deflect the end towed buoy, and the towed buoy array presents a triangular array; Positioning solution: In terms of acoustic ranging, it is necessary to unify the time base with deep towing. After the deep towing reaches the specified operating depth, it is necessary to periodically transmit acoustic signals with timestamp information so that the towed buoy can receive and process them. The hydrophone transmits the measured acoustic signals to the acoustic ranging module in real time. The acoustic ranging module calculates the emission time information of the acoustic signal and combines it with the current time information of the clock module, and uses the time difference to calculate the distance parameter information between the deep towing and the towing buoy. In terms of deep towing position solution, based on the principle of spatial distance intersection positioning, on the one hand, each towed buoy measures the distance parameter information between the deep towing and itself through acoustic ranging means, and transmits this information and the original measurement data and clock information of the towed buoy hydrophone to the acoustic positioning solution module of the deck unit in real time; on the other hand, each towed buoy obtains its own position information through satellite positioning means, and transmits this position information to the acoustic positioning solution module of the deck unit in real time; finally, the acoustic positioning solution module of the deck unit uses the least squares method with robustness to solve the position information of the underwater target in real time based on the above two aspects of data information received; in some working conditions with higher precision requirements, the original measurement data and clock information of the towed buoy hydrophones can be further integrated to perform data fusion processing to improve the accuracy of acoustic positioning solution.

Images