Multi-stage reconfigurable underwater vehicle reconstruction method based on acousto-optic fusion and Hall element

Abstract

The invention relates to the technical field of automatic control of underwater vehicles, in particular to a multi-stage reconfigurable underwater vehicle reconstruction method based on acousto-optic fusion and a Hall element, and the method comprises the steps: setting a task route point A and a point B as well as a navigation depth and a straight line tracking course angle according to a reconstruction task demand; after completing a plurality of waypoint tasks, the AUV navigates to a point B according to the own inertial navigation system; the rear AUV performs guidance reconstruction through the acoustic and optical positioning information of the front AUV; and the rear AUV adjusts and approaches the stern of the front AUV, and if a Hall element of the rear AUV detects a magnetic field, a push rod motor pushes out a push rod to complete a reconstruction task. According to the method, acoustic guidance is remotely used to enable the rear AUV to approach the front AUV, and the tail end approaches the front AUV by using a positioning result of image processing under the condition that the number of light sources is met. The method is suitable for reconstruction of various isomorphic or heterogeneous underwater robots and is high in expansibility.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater vehicle automatic control, and in particular to a multi-stage reconfigurable underwater vehicle reconstruction method and system based on acoustic-optical fusion and Hall elements. Background Art

[0002] Autonomous Underwater Vehicles (AUVs) have the advantages of autonomy, concealment, environmental adaptability, deployability, and high cost-effectiveness. They play an increasingly important role in seabed exploration, underwater rescue, seabed salvage, and marine scientific research. However, due to the constraints of their own volume, AUVs have problems such as weak endurance and limited detection range. When multiple AUVs work together, there are problems such as complex recovery processes, long recovery times, and high energy consumption. Underwater vehicle reconstruction refers to the autonomous reconstruction of multiple AUVs underwater through specific reconstruction devices carried on their heads or tails to perform subsequent long-distance voyages, energy supply, underwater recovery, and other tasks, thereby improving the endurance of AUVs and enabling them to better adapt to complex environments.

[0003] The autonomous reconstruction of autonomous underwater vehicles is a key issue for self-reconstructing AUVs. Due to the strong nonlinearity, coupling, complex environmental interference and low acoustic signal update rate of the controlled object, the complexity of autonomous reconstruction of autonomous underwater vehicles is greatly increased. The key to the problem is how to enable the self-reconstructing AUV to approach and achieve accurate reconstruction actions. Due to the low update rate of underwater acoustic signals, communication delays and near-surface multipath effects, the acoustic guidance is not ideal during terminal guidance. Visual sensors can provide high frame rate, low latency and low noise relative posture information during the reconstruction process, and have unique advantages in the autonomous reconstruction terminal stage of autonomous underwater vehicles. After the reconstruction of the autonomous underwater vehicle is completed, how to obtain accurate reconstruction feedback is an important issue. Summary of the invention

[0004] In order to solve the above technical problems, the present invention mainly solves the problems of the prior art such as complex control logic, navigation errors, large AUV energy consumption, and difficulty in reconstructing the state. The present invention provides a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements. The reconfigurable underwater vehicle in the present invention is as follows: Figure 1 As shown, the head section is equipped with an underwater camera, a Hall element and a push rod motor, and is equipped with four slotted thrusters to provide lateral and vertical forces and torques. The tail is designed with fins to carry the light source, and thrusters are designed on both sides of the tail end to replace the traditional tail thrusters.

[0005] The first object of the present invention is to provide a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements, comprising: Set the mission waypoints A and B, as well as the navigation depth and heading angle for straight-line tracking according to the reconstruction mission requirements; Among them, point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction task; point B is directly behind point A relative to the reference heading angle; The front AUV arrives at waypoint A on the surface and performs a hovering mission with depth and orientation. After the rear AUV completes several waypoint missions, it navigates according to its own inertial navigation system and arrives at point B. After the AUV reaches point B, it sets the heading angle according to its current position information, the position information of waypoint A, and straight-line tracking, and continues to navigate using the fuzzy control straight-line tracking method according to the reference heading angle, performing AUV adaptive guidance to complete the reconstruction; When the rear AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV, the rear AUV is guided by the acoustic positioning information of the front AUV; When the rear AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance. The rear AUV adjusts and approaches the stern of the front AUV. If the Hall element of the rear AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

[0006] Preferably, the reference heading angle is obtained by the following formula:

[0007] In the formula, is the straight line tracking angle; Set the heading angle for straight-line tracking;

[0008] in, k is the line tracking parameter set by the distance of the AUV from the line, L is the lateral distance between the AUV and the line.

[0009] Preferably, the lateral distance between the AUV and the straight line is calculated as follows:

[0010] In the formula, the north distance and eastward distance The value of is obtained by the following formula:

[0011]

[0012] Where R is the radius of the Earth's meridian.

[0013] Preferably, when the rear AUV still fails to detect the USBL acoustic signal after being less than 300 meters away from point A, the current reconstruction task is terminated, and it is determined whether the maximum number of attempts has been reached; if the maximum number of attempts has not been reached, the vehicle returns to point B for a new reconstruction attempt; if the maximum number of attempts has been reached, the vehicle stops and floats to wait for recovery.

[0014] Preferably, after the rear AUV arrives at point B, the acoustic positioning information detected during the navigation of the leading AUV includes: the azimuth and pitch angle of the leading AUV relative to the rear AUV and the slant distance between the leading and trailing AUVs. The information is fused with the position information output by the inertial navigation device of the rear AUV itself, and the communication delay is taken into account to obtain the absolute position of the leading AUV at the time of sending the acoustic signal. If the distance is less than 300 meters at this time, the absolute position is used as the new straight-line tracking target point.

[0015] Preferably, if the Hall element does not detect a magnetic field, the current voyage reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. If the maximum number of attempts has been reached, the AUV stops power and floats to wait for recovery; if the maximum number of attempts has not been reached, it returns to the last waypoint B for the next reconstruction task.

[0016] Preferably, when the rear AUV is less than 15 meters away from the front AUV, after the rear AUV recognizes the point light source, it uses the side auxiliary thrust control to adjust the lateral and longitudinal deviations given by the optical positioning information to an error of ≤50mm. When the axial deviation is less than 1500mm and the lateral and longitudinal deviations meet the requirements, the rear AUV posture is no longer adjusted, the current heading is maintained, and the main thrust speed is increased to move forward.

[0017] The second object of the present invention is to provide a multi-stage reconfigurable underwater vehicle reconstruction system based on acoustic-optical fusion and Hall elements, comprising: The setting module is used to set the mission waypoints A and B, as well as the navigation depth and the heading angle of the straight-line tracking according to the reconstruction mission requirements; wherein point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction mission; point B is directly behind point A relative to the reference heading angle; The early reconstruction module is used for the front AUV to arrive at waypoint A on the surface and perform the hovering task of depth determination and orientation. After the rear AUV completes several waypoint tasks, it navigates to point B according to its own inertial navigation system. After the rear AUV arrives at point B, it sets the heading angle according to its current position information, the position information of waypoint A and straight-line tracking, and continues to sail according to the reference heading angle using the fuzzy control straight-line tracking method, and performs AUV adaptive guidance to complete the reconstruction. The post-reconstruction module is used for the following AUV to guide and reconstruct through the acoustic positioning information of the front AUV when the following AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV; when the following AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance, and the following AUV adjusts and approaches the stern of the front AUV. If the Hall element of the following AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

[0018] The present invention has at least the following beneficial effects: The present invention provides a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements. The present invention uses a straight-line tracking algorithm for path tracking, adopts an acoustic-optical fusion guidance strategy, uses acoustic guidance remotely to make the rear AUV approach the front AUV, and the end uses the positioning result of image processing to approach the front AUV when the number of light sources is met. The method is applicable to the reconstruction of various isomorphic or heterogeneous underwater robots and has strong scalability.

[0019] In the method provided by the present invention, after receiving the acoustic positioning signal, the rear AUV combines the latitude and longitude output by the inertial measurement unit with the relative position measured by the acoustic positioning signal for information fusion, and considers the time system factor, so that the absolute position obtained by fusion is more accurate. Since there is no need for accurate underwater navigation position, the reconstruction requirements can still be met under long-term flight conditions, effectively reducing costs.

[0020] In the method provided by the present invention, after the stern of the front AUV and the bow of the rear AUV are stably attracted under the action of magnetic force, whether the front and rear AUVs are successfully reconstructed can be determined by whether the Hall element of the rear AUV detects a change in the magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A top view of the reconstructible AUV of the present invention; Figure 2 It is a schematic diagram of the overall autonomous reconstruction of the present invention; Figure 3 This is a single reconstruction flow chart of the present invention. DETAILED DESCRIPTION

[0022] In order to illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the following is a detailed description in conjunction with embodiments.

[0023] In order to provide a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements, the present invention uses a Hall element, a sensor element based on the Hall effect. The Hall effect means that when a conductor (usually a metal or a semiconductor) passes a current, the magnetic field placed next to the conductor causes a deviation between the current direction and the voltage. The Hall element uses this effect to measure current, detect magnetic fields, or be used as a switching element. When the reconstruction is completed, the AUV detects the magnetic field at the stern of the front AUV through the Hall element to determine whether the reconstruction is successful.

[0024] In order to achieve the above object, the present invention provides a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element, comprising: S1. Set the mission waypoints A and B, as well as the navigation depth and heading angle of the straight-line tracking according to the reconstruction mission requirements; Among them, point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction task; point B is directly behind point A relative to the reference heading angle; S2, the front AUV arrives at waypoint A on the surface and performs a hovering mission with depth and orientation. After the rear AUV completes several waypoint missions, it navigates according to its own inertial navigation system and arrives at point B. After the AUV reaches point B, it sets the heading angle according to its current position information, the position information of waypoint A, and straight-line tracking, and continues to navigate using the fuzzy control straight-line tracking method according to the reference heading angle, performing AUV adaptive guidance to complete the reconstruction; The reference heading angle is obtained by the following formula:

[0025] In the formula, is the straight line tracking angle; Set the heading angle for straight-line tracking;

[0026] in, k is the line tracking parameter set by the distance of the AUV from the line, L is the lateral distance between the AUV and the line.

[0027] The lateral distance between the AUV and the straight line is calculated as follows:

[0028] In the formula, the north distance and eastward distance The value of is obtained by the following formula:

[0029]

[0030] Where R is the radius of the Earth's meridian.

[0031] S3: When the rear AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV, the rear AUV performs guidance reconstruction based on the acoustic positioning information of the front AUV. When the rear AUV still fails to detect the USBL acoustic signal after the distance from point A is less than 300 meters, the current reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. If the maximum number of attempts has not been reached, the vehicle returns to point B for a new reconstruction attempt. If the maximum number of attempts has been reached, the vehicle stops and floats to wait for recovery.

[0032] Among them, after the rear AUV arrives at point B, the acoustic positioning information detected during the navigation of the leading AUV includes: the azimuth and pitch angle of the front AUV relative to the rear AUV, and the slant distance between the front and rear AUVs. By fusing with the position information output by the inertial navigation device of the rear AUV itself and taking into account the communication delay, the absolute position of the front AUV at the time of sending the acoustic signal is obtained. If the distance is less than 300 meters at this time, the absolute position is used as the new straight-line tracking target point.

[0033] S4. When the rear AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance. The rear AUV adjusts and approaches the stern of the front AUV. If the Hall element of the rear AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

[0034] When the rear AUV is less than 15 meters away from the front AUV, after the rear AUV recognizes the point light source, it uses the side auxiliary thrust control to adjust the lateral and longitudinal deviations given by the optical positioning information to an error of ≤50mm. When the axial deviation is less than 1500mm and the lateral and longitudinal deviations meet the requirements, the rear AUV posture is no longer adjusted, the current heading is maintained, and the main thrust speed is increased to move forward.

[0035] If the Hall element does not detect the magnetic field, the current voyage reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. If the maximum number of attempts has been reached, the AUV stops power and floats to wait for recovery; if the maximum number of attempts has not been reached, it returns to the last waypoint B for the next reconstruction task.

[0036] In order to further illustrate the multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements provided by the present invention, it is described in conjunction with the accompanying drawings.

[0037] See also Figure 1FIG. 1 is a top view of the reconfigurable AUV used in the present invention. The reconfigurable underwater vehicle head section is equipped with an underwater camera, a Hall element, and a push rod motor, and is equipped with four slot thrusters to provide lateral and vertical forces and moments, a fin is designed at the tail to carry a light source, and thrusters are designed on both sides of the tail end to replace the traditional tail thrusters.

[0038] See also Figure 2~3 As shown, a multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall elements specifically includes: Step 1: Set the mission waypoints A, B, navigation depth and heading angle for straight line tracking according to the reconstruction mission requirements , where mission waypoint A is the preset reconstruction waypoint of the leading and trailing AUVs, point B is the starting position where the trailing AUV starts the reconstruction mission (there can be multiple waypoints before point B), and point B is directly behind point A relative to the reference heading angle.

[0039] Step 2: The front AUV arrives at waypoint A on the surface and performs a hovering mission with fixed depth and orientation. The straight-line tracking sets the heading angle to , then the AUV completes several waypoint tasks in sequence and finally reaches waypoint B directly behind point A. It navigates to point B according to its own inertial navigation system; Step 3: The AUV uses the latitude and longitude output by the inertial navigation system equipment Current location, to waypoint A As the end point, As a straight line tracking setting heading angle, according to the reference heading angle The fuzzy control straight line tracking method is used to continue navigation and perform AUV adaptive guidance to complete the reconstruction. It is derived from the following formula:

[0040] in, is the straight line tracking angle, Set the heading angle for straight line tracking, It is derived from the following formula:

[0041] Wherein, k is a straight-line tracking parameter set by the distance between the AUV and the straight line; it should be noted that K is a lateral error proportional coefficient for calculating the straight-line tracking angle, and the straight line in the present invention refers to: a straight line pointing from point B to point A with a straight-line tracking heading angle, and the convergence of the lateral distance error is achieved by adjusting the reference heading angle; L is the lateral distance between the AUV and the straight line:

[0042] The north distance and eastward distance The approximate value of can be obtained by the following formula:

[0043]

[0044] Where R is the radius of the Earth's meridian. and eastward distance Both are approximate values, but both provide adequate navigation accuracy.

[0045] When the rear AUV still fails to detect the USBL acoustic signal when it is less than 300 meters away from the initially set reconstruction point A, the current reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. The maximum number of attempts refers to the time from departure from point B to completion of the reconstruction. If the current reconstruction is judged to have failed during the process, a judgment is made to decide whether to return to point B for a new reconstruction attempt. If the maximum number of attempts has not been reached, the vehicle returns to point B for a new reconstruction attempt. If the maximum number of attempts has been reached, the vehicle stops and floats up to wait for recovery. An attempt refers to the time from departure from point B to completion of the reconstruction. If the current reconstruction is judged to have failed during the process, a judgment is made to decide whether to return to point B for a new reconstruction attempt.

[0046] Step 4: When the rear AUV approaches the front AUV, the acoustic positioning information can provide: the azimuth and pitch angle of the front AUV relative to the rear AUV, and the slant distance between the front and rear AUVs, and the position information output by the rear AUV's own inertial navigation device By performing fusion and considering the communication delay, the absolute position of the front AUV at the time of sending the acoustic signal can be obtained. If the distance is less than 300 meters at this time, this position is used as the new straight-line tracking target point. Since the front AUV performs a hovering mission and the remote stage of reconstruction is not sensitive to the absolute position of the front AUV, the reconstruction requirements can be met.

[0047] Step 5: When the distance is less than 15 meters, the rear AUV slows down appropriately and adds optical guidance to perform the guidance task. When the rear AUV identifies 4 point light sources, according to the optical positioning information, the lateral deviation deltax and longitudinal deviation deltay are adjusted to about 0 (error ≤ 50mm) by using the side auxiliary thrust control. When the axial deviation deltaz is less than 1500mm and the lateral and longitudinal deviations meet the requirements, the rear AUV posture is no longer adjusted, the current heading is maintained, and the main thrust speed is increased to move forward.

[0048] Step 6: When the rear AUV adjusts and approaches the stern of the front AUV, if the Hall element of the rear AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

[0049] If the Hall element does not detect the magnetic field, the current voyage reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. The maximum number of attempts refers to the time from starting from point B to completing the reconstruction. If the reconstruction is determined to have failed during the process, a judgment is made to decide whether to return to point B for a new reconstruction attempt. If the maximum number of attempts has been reached, the AUV stops power and floats to wait for recovery; if the maximum number of attempts has not been reached, it returns to the last waypoint B for the next reconstruction task.

[0050] The present invention provides a multi-stage reconfigurable underwater vehicle reconstruction system based on acoustic-optical fusion and Hall elements, comprising: The setting module is used to set the mission waypoints A and B, as well as the navigation depth and the heading angle of the straight-line tracking according to the reconstruction mission requirements; wherein point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction mission; point B is directly behind point A relative to the reference heading angle; The early reconstruction module is used for the front AUV to arrive at waypoint A on the surface and perform the hovering task of depth determination and orientation. After the rear AUV completes several waypoint tasks, it navigates to point B according to its own inertial navigation system. After the rear AUV arrives at point B, it sets the heading angle according to its current position information, the position information of waypoint A and straight-line tracking, and continues to sail according to the reference heading angle using the fuzzy control straight-line tracking method, and performs AUV adaptive guidance to complete the reconstruction. The post-reconstruction module is used for the following AUV to guide and reconstruct through the acoustic positioning information of the front AUV when the following AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV; when the following AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance, and the following AUV adjusts and approaches the stern of the front AUV. If the Hall element of the following AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element, characterized in that: include: Set the mission waypoints A and B, as well as the navigation depth and heading angle for straight-line tracking according to the reconstruction mission requirements; Among them, point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction task; point B is directly behind point A relative to the reference heading angle; The front AUV arrives at waypoint A on the surface and performs a hovering mission with depth and orientation. After the rear AUV completes several waypoint missions, it navigates according to its own inertial navigation system and arrives at point B. After the AUV reaches point B, it sets the heading angle according to its current position information, the position information of waypoint A, and straight-line tracking, and continues to navigate using the fuzzy control straight-line tracking method according to the reference heading angle, performing AUV adaptive guidance to complete the reconstruction; When the rear AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV, the rear AUV is guided by the acoustic positioning information of the front AUV; When the rear AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance. The rear AUV adjusts and approaches the stern of the front AUV. If the Hall element of the rear AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

2. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 1 is characterized in that: The reference heading angle is given by the following formula: In the formula, is the straight line tracking angle; Set the heading angle for straight-line tracking; in, k is the line tracking parameter set by the distance of the AUV from the line, L is the lateral distance between the AUV and the line.

3. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 2 is characterized in that: The lateral distance between the AUV and the straight line is calculated as follows: In the formula, the north distance and eastward distance The value of is obtained by the following formula: Where R is the radius of the Earth's meridian.

4. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 1 is characterized in that: When the rear AUV still fails to detect the USBL acoustic signal after the distance from point A is less than 300 meters, the current reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. If the maximum number of attempts has not been reached, the vehicle returns to point B for a new reconstruction attempt. If the maximum number of attempts has been reached, the vehicle stops and floats to wait for recovery.

5. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 1 is characterized in that: After the rear AUV arrives at point B, the acoustic positioning information detected during the navigation of the leading AUV includes: the azimuth and pitch angle of the front AUV relative to the rear AUV, and the slant distance between the front and rear AUVs. By fusing it with the position information output by the rear AUV's own inertial navigation device and taking into account the communication delay, the absolute position of the front AUV at the time of sending the acoustic signal is obtained. If the distance is less than 300 meters at this time, the absolute position is used as the new straight-line tracking target point.

6. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 1 is characterized in that: If the Hall element does not detect the magnetic field, the current voyage reconstruction task is terminated and it is determined whether the maximum number of attempts has been reached. If the maximum number of attempts has been reached, the AUV stops power and floats to wait for recovery; if the maximum number of attempts has not been reached, it returns to the last waypoint B for the next reconstruction task.

7. The multi-stage reconfigurable underwater vehicle reconstruction method based on acoustic-optical fusion and Hall element according to claim 1 is characterized in that: When the rear AUV is less than 15 meters away from the front AUV, after the rear AUV recognizes the point light source, it uses the side auxiliary thrust control to adjust the lateral and longitudinal deviations given by the optical positioning information to an error of ≤50mm. When the axial deviation is less than 1500mm and the lateral and longitudinal deviations meet the requirements, the rear AUV posture is no longer adjusted, the current heading is maintained, and the main thrust speed is increased to move forward.

8. A multi-stage reconfigurable underwater vehicle reconstruction system based on acoustic-optical fusion and Hall elements, characterized in that: include: The setting module is used to set the mission waypoints A and B, as well as the navigation depth and the heading angle of the straight-line tracking according to the reconstruction mission requirements; wherein point A is the preset reconstruction waypoint of the front and rear AUVs; point B is the starting position of the rear AUV to start the reconstruction mission; point B is directly behind point A relative to the reference heading angle; The early reconstruction module is used for the front AUV to arrive at waypoint A on the surface and perform the hovering task of depth determination and orientation. After the rear AUV completes several waypoint tasks, it navigates to point B according to its own inertial navigation system. After the rear AUV arrives at point B, it sets the heading angle according to its current position information, the position information of waypoint A and straight-line tracking, and continues to sail according to the reference heading angle using the fuzzy control straight-line tracking method, and performs AUV adaptive guidance to complete the reconstruction. The post-reconstruction module is used for the following AUV to guide and reconstruct through the acoustic positioning information of the front AUV when the following AUV is less than 300 meters away from the front AUV and detects the USBL acoustic signal emitted by the front AUV; when the following AUV is less than 15 meters away from the front AUV, optical guidance is added for guidance, and the following AUV adjusts and approaches the stern of the front AUV. If the Hall element of the following AUV detects a magnetic field, the push rod motor pushes out the push rod to complete the reconstruction task.

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