Towed body control system and towed body control method of wave glider

Abstract

The invention provides a towed body control system and towed body control method of a wave glider, a sonar obstacle avoidance module detects whether there is an obstacle in the moving direction of a towed body in real time, acquires obstacle information corresponding to the towed body when detecting the obstacle, and then generates an obstacle avoidance control instruction of the towed body based on the obstacle information; the electrical control module controls the two wings, the empennage and the four propellers to execute obstacle avoidance operation based on the obstacle avoidance control instruction; the pressure depth module acquires depth information of the towed body in real time; the auxiliary sensing module acquires navigation information of the towed body and environment information corresponding to the towed body in real time; the electrical control module controls the two wings, the empennage and the four propellers to adjust the depth of the towed body based on preset depth information, depth information, navigation information and environment information. According to the invention, obstacle avoidance control and depth adjustment can be carried out on the towed body of the wave glider by using the preset depth information and the obstacle information, the depth information, the navigation information and the environment information which are acquired in real time.

Description

Technical Field

[0001] The present invention relates to the field of ocean observation technology, and in particular to a towed body control system and a towed body control method of a wave glider. Background Art

[0002] The wave glider is a unique ocean observation device. Compared with traditional ocean vehicles, the structural design of the wave glider is more special. Its structure mainly includes three parts: the float, the flexible chain and the submerged body (also known as the towing body). The float of the wave glider is usually located on the water surface, providing buoyancy and stability. The float is usually equipped with energy systems, communication equipment, control systems, etc. The flexible chain is the part that connects the float and the submerged body, usually a soft and strong chain. The submerged body is the underwater part of the wave glider. The wave glider is mainly driven by wave energy, which enables the wave glider to glide in the water, realizing long-term and large-scale ocean observation.

[0003] Wave gliders are currently ideal long-term self-sustaining mobile ocean observation platforms, but due to the structural limitations of wave gliders themselves, wave gliders only have the ability to observe on the water surface and in shallow water. To this end, the prior art has developed a winch system that can be attached to the underwater tractor of the wave glider. The winch system mounts a vertical sensor chain on the wave glider, and the sensor chain is observed in the vertical space dimension by retracting and releasing the cable.

[0004] Traditional towed body control mainly uses certain technical means to achieve control of the underwater posture and towing depth of the towed body, which are mainly divided into two technical means: active control means and passive control means. Passive control means means that the posture and depth of the towed body depend on the weight of the towed body or the fixed hydrofoil. When the towing speed of the towed body and the length of the tow cable are constant, the towed body will have a constant towing depth. Since it is impossible to actively adjust and control, the passive control means of the towed body have the disadvantages of poor flexibility and operational adaptability, low reliability and accuracy, and weak anti-interference ability. Active control means means that by adding an active control mechanism, the towed body generates sufficient forced sinking force, lateral force or pitching force, thereby achieving control of the depth or posture of the towed body. The active control means of the towed body have better flexibility and operational adaptability than the passive control means.

[0005] However, the traditional towed body control method still has the following defects: (1) the towed body depth cannot be adjusted efficiently, making it difficult to adapt to the detection needs of wave gliders in different sea areas; (2) the high-depth detection of wave gliders has a great impact on the platform's maneuverability, resulting in the limitation of the wave glider's cruising ability. These defects have brought difficulties to the observation of wave gliders. Summary of the invention

[0006] In view of this, an object of the present invention is to provide a tow body control system and a tow body control method of a wave glider, so as to alleviate the above-mentioned problems existing in the related art.

[0007] In the first aspect, an embodiment of the present invention provides a towed body control system for a wave glider, the towed body control system comprising a wave glider, a winch, a fiber optic sensor chain and a towed body, the wave glider comprising a tractor, the winch being mounted on the tractor, the first end of the fiber optic sensor chain being connected to the lower end of the winch, and the second end of the fiber optic sensor chain being detachably connected to the towed body; the towed body comprising a guide shell, two wings, a tail wing, four propellers, a sonar obstacle avoidance module, a pressure depth module, an electrical control module and an auxiliary sensor module; the guide shell is torpedo-shaped, and the front end of the guide shell is detachably connected to the second end of the fiber optic sensor chain; the two wings are symmetrically mounted on the left and right sides of the guide shell, and the two wings are connected by a coupling; the tail wing is mounted on the rear end of the guide shell; the four propellers are mounted on the guide shell and form a symmetrical structure; the electrical control module is respectively connected to the wave glider, the sonar obstacle avoidance module , the pressure depth module, the auxiliary sensing module, each of the wings, the tail wing and each of the propellers are connected; the pressure depth module, the electrical control module and the auxiliary sensing module are located in the guide shell; the sonar obstacle avoidance module is used to detect in real time whether there is an obstacle in the moving direction of the towed body, and obtain the obstacle information corresponding to the towed body when an obstacle is detected, and then generate an obstacle avoidance control instruction for the towed body based on the obstacle information; the electrical control module is used to control two wings, a tail wing and four propellers to perform obstacle avoidance operations based on the obstacle avoidance control instructions; the pressure depth module is used to obtain the depth information of the towed body in real time; the auxiliary sensing module is used to obtain the navigation information of the towed body and the environmental information corresponding to the towed body in real time; the electrical control module is also used to control the two wings, the tail wing and the four propellers to adjust the depth of the towed body based on preset depth information, the depth information, the navigation information and the environmental information.

[0008] In a second aspect, an embodiment of the present invention further provides a towed body control method for a wave glider, and the towed body control method is applied to the towed body control system described in the first aspect above, and the towed body control method includes: the sonar obstacle avoidance module detects in real time whether there is an obstacle in the moving direction of the towed body, and obtains obstacle information corresponding to the towed body when an obstacle is detected, and then generates an obstacle avoidance control instruction for the towed body based on the obstacle information; the electrical control module controls two wings, a tail wing and four propellers to perform obstacle avoidance operations based on the obstacle avoidance control instructions; the pressure depth module obtains the depth information of the towed body in real time; the auxiliary sensor module is used to obtain in real time the navigation information of the towed body and the environmental information corresponding to the towed body; the electrical control module controls the two wings, the tail wing and the four propellers to adjust the depth of the towed body based on preset depth information, the depth information, the navigation information and the environmental information.

[0009] The embodiment of the present invention provides a towed body control system and towed body control method of a wave glider, wherein the sonar obstacle avoidance module detects in real time whether there is an obstacle in the moving direction of the towed body, and obtains the obstacle information corresponding to the towed body when the obstacle is detected, and then generates the obstacle avoidance control instruction of the towed body based on the obstacle information; the electrical control module controls two wings, tail wing and four propellers to perform obstacle avoidance operation based on the obstacle avoidance control instruction; the pressure depth module obtains the depth information of the towed body in real time; the auxiliary sensor module obtains the navigation information of the towed body and the environmental information corresponding to the towed body in real time; the electrical control module controls the two wings, tail wing and four propellers to adjust the depth of the towed body based on the preset depth information, depth information, navigation information and environmental information. By adopting the above technology, the preset depth information and the obstacle information, depth information, navigation information and environmental information obtained in real time can be used to perform obstacle avoidance control and depth adjustment on the towed body of the wave glider, which can meet the detection needs of the wave glider in different sea areas, thereby improving the observation capability of the wave glider.

[0010] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0011] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 It is a schematic structural diagram of a towing control system of a wave glider in an embodiment of the present invention;

[0014] Figure 2 A schematic diagram of a structure of a towing body in an embodiment of the present invention;

[0015] Figure 3 It is another structural schematic diagram of the towing body in the embodiment of the present invention;

[0016] Figure 4 It is a schematic diagram of the working process of the trailer control system;

[0017] Figure 5 A schematic diagram of obstacle avoidance path planning in an embodiment of the present invention;

[0018] Figure 6 is a flow chart of an adaptive control algorithm for a propeller and a hydrofoil in an embodiment of the present invention;

[0019] Figure 7 It is a structural schematic diagram of a double closed-loop cascade PID control algorithm in an embodiment of the present invention;

[0020] Figure 8 The figure is a flow chart of a towing body control method of a wave glider in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described in combination with the embodiments below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] At present, the wave glider is an ideal long-term self-sustaining mobile ocean observation platform. The structure of the wave glider mainly includes three parts: the floating body, the flexible chain and the submerged body (also known as the towing body). The floating body of the wave glider is usually located on the water surface, providing buoyancy and stability. The floating body is usually equipped with energy systems, communication equipment, control systems, etc. The flexible chain is the part that connects the floating body and the submerged body, usually a soft and strong chain. The submerged body is the underwater part of the wave glider. The wave glider is mainly driven by wave energy, which enables the wave glider to glide in the water and achieve long-term and large-scale ocean observation. Traditional towing body control mainly uses certain technical means to control the underwater posture and towing depth of the towing body, but the traditional towing body control means have the following main defects: (1) The towing body depth cannot be adjusted efficiently, which is difficult to adapt to the detection needs of the wave glider in different sea areas; (2) The high-depth detection of the wave glider has a great impact on the platform's maneuverability, resulting in the limitation of the wave glider's cruising ability. These defects have brought difficulties to the observation of the wave glider.

[0023] Based on this, the towed body control system and towed body control method of a wave glider provided by the present invention can alleviate the above-mentioned problems existing in the related art.

[0024] To facilitate understanding of this embodiment, a towing body control system of a wave glider disclosed in an embodiment of the present invention is first introduced in detail.

[0025] See also Figure 1 and Figure 2 As shown, the towing body control system includes a wave glider 1, a winch 2, an optical fiber sensor chain 3 and a towing body 4. The wave glider 1 includes a tractor, the winch 2 is installed on the tractor, the first end of the optical fiber sensor chain 3 is connected to the lower end of the winch 2, and the second end of the optical fiber sensor chain 3 is detachably connected to the towing body 4; the towing body 4 includes a guide shell 41, two wings 42, a tail 43, four propellers 44, a sonar obstacle avoidance module 45, a pressure depth module 46, an electrical control module 47 and an auxiliary sensor module 48; the guide shell 41 is in the shape of a torpedo, and the front end of the guide shell 41 is connected to the first end of the optical fiber sensor chain 3. The two ends are detachably connected; the two wings 42 are symmetrically installed on the left and right sides of the guide shell 41, and the two wings 42 are connected by a coupling; the tail 43 is installed at the rear end of the guide shell 41; the four propellers 44 are installed on the guide shell 41 and form a symmetrical structure; the electrical control module 47 is respectively connected to the wave glider 1, the sonar obstacle avoidance module 45, the pressure depth module 46, the auxiliary sensor module 48, each wing 42, the tail 43 and each propeller 44; the pressure depth module 46, the electrical control module 47 and the auxiliary sensor module 48 are located in the guide shell 41.

[0026] See also Figure 1 and Figure 2 As shown, the sonar obstacle avoidance module 45 can be used to detect in real time whether there is an obstacle in the moving direction of the towing body 4, and obtain the obstacle information corresponding to the towing body 4 when the obstacle is detected, and then generate the obstacle avoidance control instruction of the towing body 4 based on the obstacle information; the electrical control module 47 can be used to control the two wings 42, the tail 43 and the four propellers 44 to perform the obstacle avoidance operation based on the obstacle avoidance control instruction;

[0027] The pressure depth module 46 can be used to obtain the depth information of the towed body 4 in real time; the auxiliary sensor module 48 can be used to obtain the navigation information of the towed body 4 and the environmental information corresponding to the towed body 4 in real time; the electrical control module 47 can also be used to control the two wings 42, the tail 43 and the four propellers 44 to adjust the depth of the towed body 4 based on preset depth information, depth information, navigation information and environmental information.

[0028] A towed body control system of a wave glider provided in an embodiment of the present invention can utilize preset depth information and real-time acquired obstacle information, depth information, navigation information and environmental information to perform obstacle avoidance control and depth adjustment on the towed body of the wave glider, thereby meeting the detection needs of the wave glider in different sea areas, thereby improving the observation capability of the wave glider.

[0029] As a possible implementation, the obstacle information may represent the relative position relationship between the obstacle and the towed body 4; based on this, see Figure 2 As shown, the sonar obstacle avoidance module 45 can also be used to plan an obstacle avoidance path for the towed body based on the obstacle information, and generate an obstacle avoidance control instruction based on the obstacle avoidance path, and then send the obstacle avoidance control instruction to the electrical control module 47.

[0030] Specifically, the sonar obstacle avoidance module 45 detects in real time whether there is an obstacle in the moving direction of the towing body 4. If an obstacle is detected, the sonar obstacle avoidance module 45 obtains the obstacle information corresponding to the towing body 4 and uses the relative position relationship between the obstacle represented by the obtained obstacle information and the towing body 4 to perform path planning to obtain an obstacle avoidance path for the towing body 4. Thereafter, an obstacle avoidance control instruction for the towing body 4 is generated using the obstacle avoidance path and the obstacle avoidance control instruction is sent to the electrical control module 47; the electrical control module 47 sends the obstacle avoidance control instruction to the two wings 42, the tail wing 43 and the four propellers 44 to control the two wings 42, the tail wing 43 and the four propellers 44 to perform obstacle avoidance operations.

[0031] As a possible implementation, the obstacle information may include a first distance between the obstacle and the towed body 4; based on this, see Figure 2 and Figure 3As shown, the sonar obstacle avoidance module 45 may include a sonar detector 451 installed on the top outer surface of the diversion housing 41 and a data processing unit 452 located in the diversion housing 41; the sonar detector 451 may be used to transmit a sound wave signal and receive an echo signal obtained after the obstacle reflects the sound wave signal when there is an obstacle on the transmission path of the sound wave signal; the data processing unit 452 may be used to determine the first distance based on the echo signal. Since the sonar detector 451 is located on the top outer surface of the diversion housing 41 of the towing body 4, it can effectively avoid the interference of the structure of the towing body 4 itself on the propagation of the sound wave signal, ensure the clarity and detection accuracy of the sonar signal, and avoid the direct influence of water turbulence on the sonar detector 451, further enhancing the working stability of the sonar detector 451.

[0032] As a possible implementation, the obstacle information may also include the size information of the obstacle; based on this, see Figure 2 and Figure 3 As shown, the data processing unit 452 can also be used to plan an obstacle avoidance path based on the first distance and size information.

[0033] Specifically, the sonar detector 451 transmits a sound wave signal. If there is an obstacle on the transmission path of the sound wave signal, the sonar detector 451 receives the echo signal obtained after the obstacle reflects the sound wave signal and sends it to the data processing unit 452; the data processing unit 452 calculates the distance between the obstacle and the towing body 4 and the size information of the obstacle using the echo signal, and uses the distance and size information to perform path planning to obtain an obstacle avoidance path for the towing body 4. Since the obstacle avoidance path is planned based on the distance between the obstacle and the towing body 4 and the obstacle size information, the obstacle avoidance path can enable the towing body 4 to avoid the obstacle more accurately, thereby improving the safety of the control of the towing body 4.

[0034] As a possible implementation, see Figure 2 and Figure 3 As shown, the sonar obstacle avoidance module 45 may also include a display unit and / or an alarm unit; the display unit may be used to visualize obstacle information when an obstacle is detected; the alarm unit may be used to generate alarm information based on the obstacle information when an obstacle is detected, and to perform an audible and visual alarm based on the alarm information. The setting of the display unit and / or the alarm unit can further improve the intuitiveness of the control of the trailer 4 through information visualization display and / or audible and visual alarm.

[0035] As a possible implementation, see Figure 3As shown, two propellers 44 are installed in pairs on the left side of the guide housing 41 and are respectively located at the front and rear of the left side of the guide housing 41, and the other two propellers 44 are installed in pairs on the right side of the guide housing 41 and are respectively located at the front and rear of the right side of the guide housing 41. The two propellers 44 installed in pairs on the same side of the guide housing 41 are symmetrically distributed front to back, the two propellers 44 installed at the front of different sides of the guide housing 41 are symmetrically distributed left to right, and the two propellers 44 installed at the rear of different sides of the guide housing 41 are symmetrically distributed left to right. Since the four propellers 44 form a symmetrical installation structure, the stability of the movement of the towing body 4 can be improved.

[0036] As a possible implementation, see Figure 2 and Figure 3 As shown, the navigation information may include acceleration information, attitude information, heading information and position information of the towed body 4; the environmental information may include water flow velocity information of the environment around the towed body 4 and the second distance between the towed body 4 and the seabed; based on this, the auxiliary sensing module 48 may include an accelerometer, a gyroscope, a magnetometer, a positioning sensor, an acoustic Doppler current meter, a laser rangefinder and a data fusion unit; the accelerometer may be used to obtain acceleration information in real time; the gyroscope may be used to obtain attitude information in real time; the magnetometer may be used to obtain heading information in real time; the positioning sensor may be used to obtain position information in real time; the acoustic Doppler current meter may be used to obtain water flow velocity information in real time; the laser rangefinder may be used to obtain the second distance between the towed body and the seabed in real time; the data fusion unit may be used to combine the navigation information and the environmental information into the environmental perception information of the towed body.

[0037] Accordingly, see Figure 2 and Figure 3 As shown, the electrical control module 47 can also be used to determine the joint control strategy for the two wings 42 and the four propellers 44 based on the preset depth information and the environmental perception information, and control the two wings 42 and the four propellers 44 to adjust the depth of the towed body 4 based on the joint control strategy; wherein the joint control strategy can be used to adjust the speed and direction of the four propellers 44 using a double closed-loop cascade PID control algorithm of angle and angular velocity, and adjust the angle of attack of the two wings 42 and the thrust of the four propellers 44 based on the preset depth information and the environmental perception information. A feedback mechanism can be introduced into the joint control strategy for the two wings 42 and the four propellers 44, and the feedback mechanism can dynamically adjust the speed, direction and thrust of the four propellers 44 and the angle of attack of the wings 42 by using the data (such as the speed and direction of the four propellers 44 and the angle of attack of the wings 42) perceived in real time by the sensors, so as to maintain the performance and stability of the towed body control system.

[0038] As a possible implementation, see Figures 1 to 3As shown, the towing body 4 may further include a fixing member 5, which may be detachably connected to the front end of the flow guide housing 41 through an electromagnetic plug-in mechanism, and the fixing member 5 is fixedly connected to the second end of the optical fiber sensor chain 3. With this design, the fixing member 5 and the flow guide housing 41 can be detachably connected by turning the electromagnetic plug-in mechanism on and off, thereby improving the flexibility of the connection between the optical fiber sensor chain 3 and the towing body 4.

[0039] For ease of understanding, the structure and working principle of the above-mentioned trailer control system are described as follows by taking a specific application as an example.

[0040] See also Figure 1 As shown, the towing control system includes a wave glider 1, a winch 2, an optical fiber sensor chain 3 and a towing body 4. The tractor part of the wave glider 1 is detachably connected to the upper end of the winch 2. The wave glider 1 provides towing kinetic energy and operating power. The first end of the optical fiber sensor chain 3 (i.e. Figure 1 The upper end of the optical fiber sensor chain 3) is detachably connected to the lower end of the winch 2, and the second end of the optical fiber sensor chain 3 (i.e. Figure 1 The lower end of the optical fiber sensor chain 3 is detachably connected to the towing body 4; a weight is arranged inside the towing body 4 so that the towing body 4 can sink into the water, and then the towing body 4 can be towed at a fixed depth by cooperating with the winch 2 to arrange and release the cable.

[0041] See also Figure 2 and Figure 3 As shown, the towing body 4 includes a guide shell 41, a wing 42, a tail wing 43, a propeller 44 (a four-wing propeller is adopted), a mechanical control module 49 (mainly used for the transmission of the wing 42, the tail wing 43, and the propeller 44), an electrical control module 47, a sonar obstacle avoidance module 45, a pressure depth module 46, and a fixing part 5 (using a sensor chain fixing cable, connected to the second end of the optical fiber sensor chain 3); the electrical control module 47 is respectively connected to the wave glider 1, the sonar obstacle avoidance module 45, the pressure depth module 46, the auxiliary sensor module 48 and the mechanical control module 49, and the mechanical control module 49 is respectively connected to the wing 42, the tail wing 43 and the propeller 44.

[0042] See also Figure 2 and Figure 3 As shown, the torpedo-shaped flow guide housing 41 is streamlined, and a towing component is provided at the front end of the flow guide housing 41. The towing component adopts an electromagnetic plug-in mechanism to realize a detachable connection between the sensor chain fixing cable and the flow guide housing 41. The electromagnetic plug-in mechanism includes a male head and a female head for plugging. The male head and the female head are respectively connected to the flow guide housing 41 and the sensor chain fixing cable, or the male head and the female head are respectively connected to the sensor chain fixing cable and the flow guide housing 41. The detachable connection between the sensor chain fixing cable and the flow guide housing 41 is realized by turning on and off the power of the electromagnetic plug-in mechanism.

[0043] See also Figure 2 and Figure 3 As shown, two wings 42 are symmetrically arranged on the left and right sides of the upper front of the deflector shell 41, and the two wings 42 are connected as a whole by a coupling. The deflector shell 41 is also provided with an angle of attack control mechanism for controlling the angle of attack of the wing 42; an angle sensor (preferably an absolute value encoder) is installed on the rotation axis of the wing 42 to monitor the current angle of attack of the hydrofoil in real time, the rotation axis of the wing 42 is a solid cylindrical steel axis and the center line of the rotation axis is the center of rotation of the wing 42, and the wing 42 adjusts the angle of attack around its rotation axis; in order to ensure the structural strength, the rotation axis of the wing 42 is preferably designed to be thick and short to reduce the bending and stress concentration that may be generated by the rotation axis during the rotation process; the tail 43 is composed of a vertical tail and a horizontal tail, and the tail 43 is connected to the deflector shell 41 as a whole. When the towing body 4 moves, the tail 43 generates a lift moment to suppress the excessive pitch of the towing body 4.

[0044] See also Figure 2 and Figure 3 As shown, four propellers 44 are distributed on the four corners of the outer surface of the guide casing 41 to form a symmetrical distribution; the propeller 44 adopts a vector propeller thruster based on a ball gear flexible shaft, and its power source is a main drive motor and two DC motors. The core component of the vector propeller thruster is a flexible shaft composed of a ball gear and a universal joint, which can meet the propulsion needs in all directions. The main drive motor keeps the propeller 44 spinning in the current posture, and the two DC motors cooperate with each other on both sides to offset the thrust, thereby deflecting the propeller 44 in all directions.

[0045] The functions of the electrical control module 47 mainly include task reception, depth control, speed control, and path tracking. Task reception is used to receive the command information sent by the wave glider 1; depth control is used to compare the actual depth of the towed body 4 with the set depth according to the received task depth information to determine the deviation between the two, and adjust the observation depth of the towed body 4 in real time; speed control is used to compare the actual speed of the towed body 4 with the set speed to determine the deviation between the two, calculate the angle and propulsion rate of the propeller 44 of the towed body 4, and the precise deflection angle of the wing 42; path tracking is used to compare the current longitude and latitude of 4 with the set longitude and latitude to determine the deviation between the two, and adjust the heading and navigation path of the towed body 4.

[0046] The sonar obstacle avoidance module 45 is a key component in the towed body control system, which is used to detect obstacles around the towed body 1 in real time and plan obstacle avoidance paths so that the towed body 4 can avoid obstacles, thereby ensuring the safe operation of the towed body 4 in a complex environment. The core components of the sonar obstacle avoidance module 45 include a sonar detector 451, a data processing unit 452 (which stores an obstacle avoidance algorithm), a first control interface, a display unit, and an alarm unit. The sonar detector 451 is the basic equipment of the sonar obstacle avoidance module 45, which is responsible for emitting sound wave signals and receiving echo signals reflected by obstacles. The data processing unit 452 is responsible for converting the echo signals collected by the sonar detector 451 into useful information (such as the distance between the obstacle and the towed body 4 and the shape and size of the obstacle, etc.). The data obtained after processing by the data processing unit 452 can help the towed body control system understand the distance, size, and position of the obstacle. The data processing unit 452 includes: a signal processor for filtering and amplifying the echo signal; an obstacle detection algorithm for identifying the position and characteristics of obstacles; an obstacle avoidance algorithm for calculating the obstacle avoidance path using the processed sonar data and generating control instructions for adjusting the movement of the towed body 4. The first control interface is responsible for transmitting the control instructions generated by the obstacle avoidance algorithm to the electrical control module 47, so that the electrical control module 47 sends the control instructions to the mechanical control module 49, thereby controlling the propeller 44, the wing 42 and other actuators through the mechanical control module 49 to implement the path adjustment and motion control of the towed body 4. The display unit is used to visualize the obstacle detection results through the display screen to show the position, distance and state of the obstacle, and the alarm unit is used to issue an alarm when necessary to remind the operator through sound or visual signals that there is an obstacle approaching the towed body 4, thereby realizing real-time monitoring and response of the towed body 4 to the obstacle.

[0047] The core components of the pressure depth module 46 include a pressure depth gauge, a D / A converter (i.e., a digital-to-analog converter), and a second control interface. The core function of the pressure depth module 46 is to ensure that the towed body 4 can operate stably within a preset depth range and provide necessary data support for the depth control and motion adjustment of the towed body 4. The pressure depth gauge is used to calculate the depth by measuring the underwater pressure change to output the depth data, the D / A converter is used to convert the depth data into an analog signal, and the second control interface is used to transmit the analog signal to the electrical control module 47 so that the electrical control module 47 controls the propeller 44, the wing 42, the tail 43, etc. through the mechanical control module 49 to perform depth control and motion adjustment on the towed body 4.

[0048] The auxiliary sensing module 48 mainly includes an accelerometer, a gyroscope, a magnetometer, a positioning sensor (GPS), an acoustic Doppler current meter, a laser rangefinder, and a data fusion unit. The accelerometer is used to measure the acceleration changes of the towed body 4 in all directions, and the gyroscope is used to measure the angular velocity of the towed body 4. The data measured by the accelerometer and the gyroscope can help the towed body 4 adjust its own posture and motion trajectory in real time to ensure the stable operation of the towed body 4 underwater. The magnetometer is used to provide the direction information (i.e., heading) of the towed body 4 relative to the earth's magnetic field by detecting the changes in the earth's magnetic field, and the GPS is used to provide the precise position data of the towed body 4 underwater to help the towed body 4 track the path. The acoustic Doppler current meter is used to measure the speed and direction of the water flow. The laser rangefinder is used to monitor the distance between the towed body 4 and the seabed in real time. The data fusion unit is used to integrate data from various sensors and optimize the integrated data (such as deduplication, denoising, etc.) to generate comprehensive environmental perception information, and transmit the environmental perception information to the electrical control module 47 so that the electrical control module 47 can control the respective working states of the wings 42, propellers 44, and tail 43 through the mechanical control module 49.

[0049] The working process of the towed body control system is mainly as follows: when the towed body 4 adjusts the depth to ascend or dive, the safety of the water area is detected in real time. If an obstacle appears, the towed body 4 stops moving, and the course of the towed body 4 is changed by the joint control of the wing 42 and the propeller 44. If no obstacle is detected, the towed body 4 continues to ascend or dive according to the original route until the predetermined depth is reached. The pressure depth module 46 is fixedly installed inside the guide shell 5 to collect depth information; the sonar detector 451 is installed outside the guide shell 5 to collect sonar data; the auxiliary sensor module 48 receives the data collected by the accelerometer, gyroscope, magnetometer, GPS, acoustic Doppler current meter, and laser rangefinder, and optimizes the received data, and then transmits the optimized data to the electrical control module 47, so that the electrical control module 47 controls the wing 42, propeller 44, and tail 43 through the mechanical control module 49.

[0050] like Figure 4 As shown, the workflow of the trailer control system can mainly include:

[0051] Step 1: setting a predetermined depth of the drag body 4.

[0052] Step 2: The sonar obstacle avoidance module 45 and the pressure depth module 46 obtain environmental information.

[0053] Specifically, the sonar detector 451 collects sonar data of the towed body 4 , the data processing unit converts the sonar data into required information, and the pressure depth meter collects depth data of the towed body 4 .

[0054] Step 3: the sonar obstacle avoidance module 45 determines whether there is an obstacle within the detection range of the sonar detector 451.

[0055] If there is no obstacle within the detection range of the sonar detector 451, steps 4 to 7 are executed; if there is an obstacle within the detection range of the sonar detector 451, step 8 is executed (ie the towing body 4 switches to a circuitous navigation path).

[0056] Step 4: The auxiliary sensing module 48 optimizes and processes the data collected by the accelerometer, gyroscope, magnetometer, positioning sensor (GPS), acoustic Doppler flow meter, and laser rangefinder.

[0057] Step 5: the electrical control module 47 controls the speed and posture of the towing body 4.

[0058] Specifically, the electrical control module 47 controls the working states of the wings 42 , the propellers 44 , and the tail 43 through the mechanical control module 49 to adjust the speed and attitude of the towing body 4 .

[0059] Step 6: The sonar obstacle avoidance module 45 and the pressure depth module 46 obtain environmental information.

[0060] Step 7: The electrical control module 47 determines whether the drag body 4 has reached a predetermined depth.

[0061] If the towed body 4 reaches the predetermined depth, step 9 is executed (i.e. the towed body 4 maintains the current posture and current depth unchanged), and the process returns to step 2; if the towed body 4 does not reach the predetermined depth, step 10 is executed (i.e. the towed body 4 maintains the current sailing direction unchanged), and the process returns to step 2.

[0062] Step 8: the towed body 4 switches to a circuitous navigation path.

[0063] Specifically, in the above step 8, the data processing unit 452 uses the obstacle avoidance algorithm to plan a circuitous navigation path and generates a control instruction based on the circuitous navigation path. The first control interface transmits the control instruction to the electrical control module 47, and the electrical control module 47 sends the control instruction to the mechanical control module 49. The mechanical control module 49 controls the propeller 44, the wing 42, and the tail 43 to work, so that the towed body 4 switches to the circuitous navigation path to avoid obstacles. Figure 5 As shown in the figure, there are three main ways to plan a detour route:

[0064] 1) Elliptical detour path planning: When an obstacle 6 is detected, according to the acquired obstacle information, the maximum radius of the obstacle 6 is used as the minor axis of the ellipse of the new path, and the distance from the obstacle 6 to the towed body 4 is used as the major axis of the ellipse, so as to plan an elliptical curve 501 to avoid the obstacle 6. This path planning method is more flexible, suitable for larger or irregular obstacles, and has high efficiency and less time consumption;

[0065] 2) Multi-fold line segment detour path planning: When an obstacle 6 is detected, the maximum radius of the obstacle 6 is used as the path safety vertex, and the vehicle is quickly raised or lowered. The sum of the distance from the obstacle to the towed body 4 and the maximum radius of the obstacle 6 is used as the obstacle avoidance navigation distance, and a multi-fold line segment detour path 502 is planned. This path planning method is intuitive and simple, and is suitable for more complex obstacle groups, so as to avoid excessive detours of the towed body 4;

[0066] 3) Extended arc detour path planning: When an obstacle 6 is detected, an arc detour path 503 with a radius larger than the maximum radius of the obstacle 6 is generated around the obstacle 6 (i.e., the ratio between the radius of the arc detour path 503 and the maximum radius of the obstacle 6 is greater than 1), so as to ensure that the trailer 4 can bypass the obstacle 6. Specifically, the radius of the arc detour path 503 can be set according to the following formula: R path =K×R OBSTACLE , K>1, is a safety factor; R path is the radius of the circular arc detour path 503, R ORSTACLE is the maximum radius of the obstacle 6; the towing body 4 detouring along the arc-shaped circuitous path 503 can ensure that the towing body 4 and the obstacle 6 maintain a sufficient safe distance, which is suitable for avoiding a single obstacle in a simple environment, and effectively reduces the risk of contact between the towing body 4 and the obstacle 6.

[0067] Step 9: The dragged body 4 maintains the current posture and current depth unchanged.

[0068] Step 10: the towed body 4 maintains the current sailing direction unchanged.

[0069] In the above steps 1 to 10, when the towed body 4 needs to adjust its depth, the sonar obstacle avoidance module 45 is used to detect the water conditions to ensure the safety of the towed body 4. If an obstacle suddenly appears, the sonar detection module 11 will send the detected obstacle information to the electrical control module 47. The electrical control module 47 will plan an obstacle avoidance path according to the obstacle information and generate an obstacle avoidance control instruction according to the obstacle avoidance path, and then send the obstacle avoidance control instruction to the mechanical control module 49, so that the propeller 44 and the wing 42 can be jointly controlled by the mechanical control module 49, thereby changing the heading and speed of the towed body 4 to avoid obstacles near the towed body 4 and quickly restore the towed body 4 to its original working state.

[0070] Specifically, the joint control logic of the propeller 44 and the wing 42 mainly includes: after receiving the obstacle avoidance control command, the electrical control module 47 first optimizes the obtained control command data, and then forms a unified control strategy by integrating the control signals of the propeller 44 and the wing 42. The propeller 44 is mainly responsible for adjusting the thrust and speed of the towed body 4, while the wing 42 is used to adjust the attitude and direction of the towed body 4. This joint control method can quickly respond to the appearance of obstacles near the towed body 4 while ensuring the stability of the movement of the towed body 4. When the obstacle is far in front of the towed body 4 (that is, the distance between the obstacle and the towed body 4 is not less than the preset distance threshold), the towed body control system preferentially uses the wing 42 to adjust the heading of the towed body 4 to reduce the impact of the obstacle avoidance process of the towed body 4 on the speed of the towed body 4. When the obstacle is close to the towed body 4 (that is, the distance between the obstacle and the towed body 4 is less than the preset distance threshold), the towed body control system will increase the thrust of the propeller 4 to increase the response speed of the towed body 4, and appropriately adjust the angle of the wing 42 to enable the towed body 4 to quickly avoid the obstacle. During the joint control process, the control priority of the propeller 44 and the wing 42 can be dynamically adjusted according to the distance between the obstacle and the towing body 4 and the position of the obstacle relative to the towing body 4 .

[0071] The control strategy of the propeller 44 is mainly that the propeller 44 dynamically adjusts the magnitude and direction of the thrust according to the optimized heading command and speed command. The towed body control system can control the independent operation of each propeller 44 to achieve more precise control; for example, when the towed body 4 needs to make a sharp turn, the towed body control system can reduce the thrust of the propeller 44 on one side and increase the thrust of the propeller 44 on the other side to quickly change the heading of the towed body 4. The towed body control system can control the forward speed of the towed body 4 by adjusting the speed of the propeller 44. At this time, the rapid responsiveness of the propeller 44 can enable the towed body 4 to quickly avoid obstacles and quickly return to the originally set speed after the obstacle avoidance is completed.

[0072] The towed body control system can control the posture of the towed body 4 by controlling the wing 42 to adjust its own angle. In particular, when the towed body 4 encounters a lateral obstacle, the wing 42 can adjust the lateral motion trajectory of the towed body 4 by tilting to avoid the collision between the towed body 4 and the obstacle. In the joint control of the propeller 44 and the wing 42, the wing 42 can further enhance the steering effect when the towed body 4 turns, and reduce the side slip and speed loss caused by the propeller 44 adjusting the thrust. At the same time, in the process of recovering the course after the towed body 4 avoids the obstacle, the wing 42 ensures that the towed body 4 can return to the original course smoothly and accurately by finely adjusting its own angle.

[0073] When the wave glider 1 faces different sea conditions, the joint control strategy of the propeller 44 and the wing 42 can adapt to different environmental conditions and achieve complex operation tasks.

[0074] Specifically, in view of the situation that the towed body 4 of the wave glider 1 needs to maintain a stable depth to collect accurate data under various sea conditions, in the face of strong sea currents or waves, the joint control of the propeller 44 and the wing 42 can help the towed body 4 maintain a stable depth. The propeller 44 provides additional thrust to resist the impact of the sea current and prevent the wave glider 1 from deviating from the predetermined track; at the same time, after transmitting the environmental data obtained according to the pressure depth module 46 and the auxiliary sensor module 48 to the electrical control module 47, the electrical control module 47 will use this part of the environmental data to calculate the attitude angle deviation and depth deviation of the towed body 4 caused by the sea current and compare the actual depth of the towed body 4 with the predetermined depth. When the actual depth is lower than the predetermined depth, the electrical control module 47 controls the wing 42 to increase the angle of attack through the mechanical control module 49 to increase the lift generated by the wing 42 so that the towed body 4 is adjusted upward to the predetermined depth. When the actual depth is higher than the predetermined depth, the electrical control module 47 controls the wing 42 to decrease the angle of attack through the mechanical control module 49 to reduce the lift generated by the wing 42 so that the towed body 4 is adjusted downward to the predetermined depth. In addition, the electrical control module 47 can use a preset control algorithm to set relevant control parameters, and adjust the change amplitude of the angle of attack of the wing 42 according to the depth deviation. The greater the depth deviation, the greater the increase amplitude of the angle of attack of the wing 42. The electrical control module 47 can also process the long-term accumulated depth error according to the environmental data to ensure that the actual depth of the towed body 4 can be stabilized near the predetermined depth, and compensate for the rapidly changing environmental conditions in advance in response to the rate of change of the actual depth of the towed body 4, so as to maintain the stability of the attitude and depth of the towed body 4.

[0075] Specifically, in view of the situation that the towed body 4 of the wave glider 1 sails in an environment with an uneven seabed and complex sea currents, when the auxiliary sensor module 48 detects a sudden change in the seabed height, the propeller 44 can quickly adjust the thrust and speed according to the sensor feedback information to help the towed body 4 quickly adapt to the change in the seabed height so as to avoid the towed body 4 from colliding due to inertia, and the angle of attack of the wing 42 is dynamically adjusted according to the change in the seabed height to maintain the stable posture of the towed body 4 when the seabed height changes, thereby preventing the towed body 4 from tilting or losing stability due to changes in the seabed terrain. The auxiliary sensor module 48 measures the distance between the towed body 4 and the seabed in real time. As the towed body 4 sails in an area with an uneven seabed, the sensor continuously provides height difference data, and the towed body control system calculates the change in the distance between the towed body 4 and the seabed according to the real-time data obtained by the sensor. If the towed body control system detects that the seabed height in front of the towed body 4 increases or decreases, it is determined that the towed body 4 is about to reach an inclined area. The towed body control system predicts the upcoming tilt angle based on the sensor data and estimates the need for adjusting the angle of attack of the wing 42 in advance according to the rate of change of the seabed terrain, and the real-time data is sent to the closed-loop control process. In the closed-loop control process, the towed body control system calculates the required angle of attack adjustment of the wing 42 and the thrust and angle of the propeller 44 through the controller algorithm. When the sensor detects that the terrain in front of the towed body 4 rises sharply, the electrical control module 47 controls the angle of attack of the wing 42 to increase rapidly through the mechanical control module 49 to lift the towed body 4 and prevent the towed body 4 from hitting the seabed. When the sensor detects that the terrain in front of the towed body 4 gradually drops, the electrical control module 47 controls the angle of attack of the wing 42 to decrease accordingly through the mechanical control module 49 to ensure that the towed body 4 smoothly follows the terrain changes and slides down, thereby preventing the towed body 4 from being over-lifted and causing the towed body 4 to become unstable. At the same time, the propeller 44 provides additional thrust to help the towed body 4 to rise quickly. When the towed body 4 encounters a protruding seabed obstacle, the electrical control module 47 controls the propeller 44 to reduce its speed in a short period of time through the mechanical control module 49 to better control the descending speed of the towed body 4 and ensure that the towed body 4 can smoothly cross the obstacle. When the velocity of the ocean current changes frequently, the electrical control module 47 adjusts the rotation speed and thrust direction of the propeller 44 in real time through the mechanical control module 49 according to the feedback from the velocity sensor (i.e., acoustic Doppler anemometer) to offset the influence of the lateral or longitudinal velocity of the ocean current on the towing body 4, thereby ensuring that the towing body 4 remains on the predetermined route; under the influence of strong ocean currents, the electrical control module 47 will continuously adjust the thrust of the propeller 44 through the mechanical control module 49 to keep the towing body 4 in a horizontal posture, thereby preventing the posture of the towing body 4 from deviating from the preset posture due to side currents or upwellings, thereby ensuring the stability of the posture of the towing body 4.

[0076] Specifically, in the case where the towed body 4 of the wave glider 1 needs to hover, the electrical control module 47 receives the feedback information of the pressure depth gauge and the auxiliary sensor module 48 in real time. The electrical control module 47 calculates whether the current angle of attack of the wing 42 is appropriate based on the received depth feedback data. If the pressure depth gauge detects that the actual depth of the towed body 4 deviates from the preset value (i.e., the predetermined depth), the electrical control module 47 will immediately adjust the angle of attack of the wing 42 through the mechanical control module 49 to increase or decrease the lift generated by the wing 42. During this period, the thrust provided by the propeller 44 can help the towed body 4 quickly reach the predetermined hovering position. When the towed body 4 reaches the predetermined hovering position, in order to maintain the hovering state of the towed body 4, the wing 42 needs to provide an upward lift to make the lift equal to the gravity of the towed body 4; when the towed body 4 sinks slightly (that is, the actual depth of the towed body 4 is lower than the predetermined depth), the electrical control module 47 will detect this change and quickly adjust the angle of attack of the wing 42 through the mechanical control module 49, so that the wing 42 generates a greater lift, thereby offsetting the sinking trend of the towed body 4; if the towed body 4 floats due to water flow disturbance, the electrical control module 47 will reduce the angle of attack of the wing 42 through the mechanical control module 49 to reduce the lift generated by the wing 42. The angle of attack deflection (i.e., the amplitude of change) of the wing 42 is determined by the depth deviation. After the towed body 4 is rebalanced at the predetermined depth, the thrust of the propeller 44 will be maintained at a relatively low level, and the propeller 44 will only provide auxiliary thrust when necessary. When the electrical control module 47 determines, based on the real-time data collected by the auxiliary sensor module 48, that the towed body 4 has deviated from its position due to water flow disturbance or other factors, the electrical control module 47 will rapidly increase the thrust generated by the propeller 44 through the mechanical control module 49 to restore the towed body 4 to the predetermined hovering position. At this time, the control method of the propeller 44 is to gradually adjust the thrust according to the deviation between the current position of the towed body 4 and the predetermined hovering position until the towed body 4 returns to the predetermined hovering position.

[0077] Through the joint control of the propeller 44 and the wing 42, the towed body control system can realize high-precision multiple operations in a complex underwater environment, quickly adjust the posture and position of the towed body 4, and ensure that the towed body 4 performs effective operations at the designated position.

[0078] Specifically, Figure 6 As shown, the adaptive control algorithm flow of the propeller 44 and the wing 42 mainly includes the following steps:

[0079] Step S601, establishing a drag body model.

[0080] According to the mass m and inertia matrix I of the towed body 4, the translation equation and rotation equation of the towed body 4 are established:

[0081]

[0082]

[0083] Wherein, v is the velocity direction vector of the towed body 4, F is the sum of the external forces of the towed body 4 (including the buoyancy F of the towed body 4). b 、The gravity F of the drag body 4 g , the lift F of wing 42 w and the thrust F of propeller 44 p ), ω is the angular velocity vector of the towing body 4, and M is the total external torque of the towing body 4 (including the torques of the propeller 44 and the wing 42).

[0084] Step S602: real-time error calculation.

[0085] First, the target attitude (i.e., predetermined attitude, such as target pitch angle, target yaw angle, and target roll angle) and target position of the towed body 4 are set, and then the data of the pressure depth gauge, attitude sensor, and position sensor are integrated using data fusion technology. Then, according to the current position (i.e., actual position) and current attitude (i.e., actual attitude, including actual pitch angle, actual yaw angle, and actual roll angle) of the towed body 4 acquired in real time, the position error between the actual position of the towed body 4 and the target position, and the attitude error between the actual attitude of the towed body 4 and the target attitude are calculated using the following formula.

[0086] e p =p targent -p current

[0087] e θ =θ targent -θ current

[0088] Among them, e p is the position error, e θ is the attitude error, p targent is the target position, p current is the actual position, θ targent is the target attitude angle, θ current is the actual attitude angle.

[0089] Step S603: control law design.

[0090] like Figure 7As shown, the control algorithm of the propeller 44 adopts a dual closed-loop cascade PID control structure. The control algorithm achieves precise control of the propeller 44 through two closed-loop PID controllers (i.e., the angle loop PID controller and the angular velocity loop PID controller). The parameters of the two closed-loop PID controllers are adjusted in real time to enhance the adaptability and stability of the towed body control system under different working conditions, so that the towed body control system can respond quickly and maintain the predetermined posture or target position of the towed body. In the control algorithm of the propeller 44, the fuzzy reasoning module is used to perform fuzzy reasoning based on the angle error and its rate of change to dynamically adjust the parameters of the angle loop PID controller (including the proportional gain coefficient, the integral gain coefficient, and the differential gain coefficient), so that the propeller 44 can still maintain an efficient and stable operating state in a complex and uncertain underwater environment. The following is the parameter setting method of the dual closed-loop cascade PID control algorithm:

[0091] (i) Outer loop P (i.e., the proportional term of the angle loop) setting: The outer loop P starts from a smaller value and gradually increases. The fuzzy reasoning module will dynamically adjust the outer loop P value according to the real-time angle error and the angle error change rate, so that the quadcopter propeller always maintains a stable response under different working conditions. When the outer loop P value gradually increases, the quadcopter propeller may show a sense of resistance. Fuzzy control will avoid high-frequency vibration or divergence caused by excessive outer loop P value, ensuring that the towed body control system responds quickly while maintaining stability.

[0092] (ii) Adjustment of the outer loop I (i.e., the integral term of the angle loop): The outer loop I is used to eliminate the static error of the angle. Through fuzzy control, the towed body control system can automatically adjust the outer loop I value according to the error and static error of the current angle, ensuring that the quadcopter propeller can stabilize the towed body 4 at the target position without falling. Fuzzy control will prevent the towed body control system from becoming unstable and divergent due to an excessively large I value, ensuring that the towed body control system eliminates the static error of the angle while maintaining stability.

[0093] (III) Outer loop D (i.e., the differential term of the angle loop) setting: Outer loop D is used to affect the rate of change of the angle error, and there is a high risk of introducing noise into the angle loop. Fuzzy control dynamically adjusts the outer loop D value by judging the rate of change of the angle error to reduce the impact of noise. Fuzzy control can also be combined with filtering technology (such as sliding filtering or IIR filtering) to reduce the impact of high-frequency vibration, thereby ensuring that the return performance of the quadcopter propeller is still good under the influence of noise.

[0094] (IV) Inner loop P (i.e., proportional term of angular velocity loop) tuning: After completing the adjustment of the outer loop PID control parameters, the towed body control system should be able to stabilize the towed body 4 at a predetermined angular position. The inner loop P value can be dynamically adjusted based on the angular velocity error, so that the quadcopter propeller can effectively restore the towed body 4 to a balanced state at different angular velocities, ensuring that the towed body control system will not be overly sensitive or divergent when adjusting the inner loop P value, thereby enhancing the response speed and sensitivity of the towed body control system.

[0095] The above-mentioned double closed-loop cascade PID control algorithm of the quadcopter propeller is conducive to enhancing the load impact resistance of the towed body 4 in water, so that the towed body 4 can perform dynamic adjustments more quickly and accurately when facing complex situations such as flow velocity fluctuations.

[0096] The joint control strategy of the propeller 44 and the wing 42 is mainly to adjust the angle of attack α of the wing 42 w and propeller 44 thrust F P The attitude and depth of the towing body 4 can be controlled by combined adjustment. The thrust of the propeller 44 and the angle of attack of the wing 42 can be adjusted according to the following formula:

[0097]

[0098]

[0099] Among them, K p is the proportional gain coefficient, e z is the depth error, K d is the differential gain coefficient, e θ is the attitude error of the towed body 4, K i is the integral gain coefficient, and e(τ) is the attitude angle of the towed body 4 at time τ.

[0100] Step S604: adaptively adjust parameters.

[0101] According to the real-time error calculated in step S602, an error analysis can be performed to analyze the error change trend, so as to distinguish whether the error is a short-term fluctuation caused by environmental disturbance or a long-term deviation caused by improper controller parameters. The best initial parameter configuration scheme can be obtained by statistically analyzing the historical data of different sea conditions; when there is no prior data, the default general parameters can be used as the initial parameter configuration scheme. The controller gain can be dynamically adjusted according to the real-time error. When the error change rate increases, the controller gain is increased to speed up the response speed. When the error is small and the change is stable, the controller gain is reduced to reduce the oscillation of the towed body control system. The controller gain can be adaptively adjusted according to different environmental conditions (such as water flow velocity, turbulence intensity, etc.), and different controller gain adjustment strategies can be set, such as adjusting the proportional gain coefficient based on the error change rate, adjusting the controller gain coefficient based on the sea condition, etc.

[0102] Step S605: adaptive update learning.

[0103] The parameters of the control algorithm can be continuously optimized through online learning. Specifically, reinforcement learning algorithms or adaptive neural networks can be introduced to continuously correct the parameters of the control algorithm through real-time feedback, thereby learning the optimal control strategy.

[0104] Step S606: fault detection and redundancy detection.

[0105] The working status of the wing 42, propeller 44 and tail 43 are monitored in real time by redundant sensors (i.e., main sensors and backup sensors of the same type of sensors are set). Vibration analysis (i.e., collecting vibration data and analyzing the vibration data by installing sensors) and temperature monitoring (i.e., monitoring temperature by installing sensors) and other technical means can be used to identify faults and issue early warning signals in a timely manner. When a fault is detected, the redundant control strategy is activated to ensure the continuous operation of the towed body control system. Multi-level redundant control strategies (such as multi-wing coordinated control, multi-propeller power distribution adjustment, etc.) can be designed to ensure that the towed body control system can still maintain stability in the event of a single point failure. After the fault is recovered, the towed body control system automatically switches back to the normal control mode and reminds the operator to check through an alarm. The towed body control system can also record fault information in the form of a log to facilitate subsequent maintenance and fault analysis.

[0106] The beneficial effects of the above-mentioned trailer control system are mainly reflected in the following aspects:

[0107] The torpedo-shaped guide shell is used to significantly reduce the fluid resistance of the towed body during underwater movement, reduce turbulence and noise, and give the towed body good hydrodynamic performance.

[0108] The sonar detector is located on the top outer surface of the guide shell, which can effectively avoid the interference of the towed body's own structure on the propagation of sound wave signals, ensure the clarity and detection accuracy of the sonar signal, and enhance the stability of the towed body control.

[0109] The use of a vector propeller thruster based on a ball gear flexible shaft achieves high-precision directional control and all-round flexible maneuverability of the towed body in an underwater environment. The synergistic effect of the main drive motor and the DC motor enables the propeller to quickly adjust the thrust direction, improving the response speed and stability of the towed body control, thereby enhancing the adaptability and operational performance of the towed body in complex underwater operations.

[0110] The towed body has good stability and flexible attitude adjustment. Based on the real-time attitude data of the towed body, the wings, tail wing and four-axis rotor propeller can be used to accurately adjust the attitude of the towed body. Specifically, the up and down floating of the towed body is achieved by controlling the angle of the wings, the stability of the towed body's heading is maintained by the tail wing to avoid the towed body from yaw, and the attitude of the towed body is further fine-tuned by adjusting the thrust direction and thrust size of the four-axis rotor propeller, so that the towed body can maintain stable navigation and quickly adjust its own attitude in various underwater operations, ensuring the reliability and flexibility of the towed body when performing tasks.

[0111] Based on the above towed body control system, an embodiment of the present invention further provides a towed body control method for a wave glider, which can be applied to the above towed body control system. Figure 8 As shown, the drag body control method may include the following steps:

[0112] In step S801 , the sonar obstacle avoidance module 45 detects in real time whether there is an obstacle in the moving direction of the towed body 4 , and obtains obstacle information corresponding to the towed body 4 when an obstacle is detected, and then generates an obstacle avoidance control instruction for the towed body 4 based on the obstacle information.

[0113] In step S802 , the electrical control module 47 controls the two wings 42 , the tail wing 43 and the four propellers 44 to perform an obstacle avoidance operation based on the obstacle avoidance control instruction.

[0114] Step S803 : the pressure-depth module 46 acquires the depth information of the towed body 4 in real time.

[0115] In step S804 , the auxiliary sensor module 48 obtains the navigation information of the towed body 4 and the environment information corresponding to the towed body 4 in real time.

[0116] In step S805 , the electrical control module 47 controls the two wings 42 , the tail 43 and the four propellers 44 to adjust the depth of the towing body 4 based on the preset depth information, the depth information, the navigation information and the environmental information.

[0117] The obstacle information can represent the relative positional relationship between the obstacle and the towing body 4; based on this, in the above step S801, the sonar obstacle avoidance module 45 generates an obstacle avoidance control instruction for the towing body 4 based on the obstacle information, which may include: the sonar obstacle avoidance module 45 plans an obstacle avoidance path for the towing body 4 based on the obstacle information, generates an obstacle avoidance control instruction based on the obstacle avoidance path, and then sends the obstacle avoidance control instruction to the electrical control module 47.

[0118] The obstacle information may include a first distance between the obstacle and the towing body 4; the sonar obstacle avoidance module 45 may include a sonar detector 451 installed on the top outer surface of the deflector housing 41 and a data processing unit 452 located in the deflector housing 41; based on this, in the above step S801, the sonar obstacle avoidance module 45 obtains the obstacle information corresponding to the towing body 4, which may include: the sonar detector 451 transmits a sound wave signal and receives an echo signal obtained after the obstacle reflects the sound wave signal when there is an obstacle on the transmission path of the sound wave signal; the data processing unit 452 determines the first distance based on the echo signal.

[0119] The sonar obstacle avoidance module 45 may further include a display unit and / or an alarm unit; based on this, the above-mentioned towed body control method may further include: the display unit visually displays the obstacle information when an obstacle is detected; and / or the alarm unit generates alarm information based on the obstacle information when an obstacle is detected, and performs an audible and visual alarm based on the alarm information.

[0120] The navigation information may include acceleration information, attitude information, heading information and position information of the towed body 4; the environmental information may include water flow velocity information of the environment around the towed body 4 and the second distance between the towed body 4 and the seabed; the auxiliary sensor module 48 may include an accelerometer, a gyroscope, a magnetometer, a positioning sensor, an acoustic Doppler current meter, a laser rangefinder and a data fusion unit;

[0121] Based on this, the above step S804 (i.e. the auxiliary sensor module 48 acquires the navigation information of the towed body 4 and the environmental information corresponding to the towed body 4 in real time) may include: the accelerometer acquires the acceleration information in real time; the gyroscope acquires the attitude information in real time; the magnetometer acquires the heading information in real time; the positioning sensor acquires the position information in real time; the acoustic Doppler current meter acquires the water flow velocity information in real time; the laser rangefinder acquires the second distance between the towed body and the seabed in real time. The above towed body control method may also include: the data fusion unit combines the navigation information and the environmental information into the environmental perception information of the towed body 4.

[0122] The above-mentioned step S805 (i.e., the electrical control module 47 controls the two wings 42, the tail 43 and the four propellers 44 to adjust the depth of the towed body 4 based on the preset depth information, depth information, navigation information and environmental information) may include: the electrical control module 47 determines a joint control strategy for the two wings 42 and the four propellers 44 based on the preset depth information and environmental perception information, and controls the two wings 42 and the four propellers 44 to adjust the depth of the towed body 4 based on the joint control strategy; wherein the joint control strategy can be used to adjust the rotation speed and direction of the four propellers 44 using a dual closed-loop cascade PID control algorithm of angle and angular velocity, and adjust the angle of attack of the two wings 42 and the thrust of the four propellers 44 based on the preset depth information and environmental perception information.

[0123] The obstacle information may also include the size information of the obstacle; based on this, the step of the sonar obstacle avoidance module 45 planning the obstacle avoidance path of the towed body 4 based on the obstacle information may include: the data processing unit 452 plans the obstacle avoidance path based on the first distance and the size information.

[0124] The towed body control method of the wave glider provided in the embodiment of the present invention has the same implementation principle and technical effects as those of the aforementioned towed body control system embodiment. For the sake of brief description, for matters not mentioned in the towed body control method embodiment, reference may be made to the corresponding contents in the aforementioned towed body control system embodiment.

[0125] Unless otherwise specifically stated, the relative steps, numerical expressions and values ​​of the components and steps set forth in these embodiments do not limit the scope of the present invention.

[0126] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0127] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0128] Finally, it should be noted that the above-described embodiments are only specific implementations of the present invention, which are used to illustrate the technical solutions of the present invention, rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention is described in detail with reference to the above-described embodiments, ordinary technicians in the field should understand that any technician familiar with the technical field can still modify the technical solutions recorded in the above-described embodiments within the technical scope disclosed by the present invention, or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A towing body control system of a wave glider, characterized in that: The towing body control system comprises a wave glider, a winch, an optical fiber sensor chain and a towing body, wherein the wave glider comprises a tractor, the winch is mounted on the tractor, the first end of the optical fiber sensor chain is connected to the lower end of the winch, and the second end of the optical fiber sensor chain is detachably connected to the towing body; The towing body includes a guide shell, two wings, a tail wing, four propellers, a sonar obstacle avoidance module, a pressure depth module, an electrical control module and an auxiliary sensor module; the guide shell is in the shape of a torpedo, and the front end of the guide shell is detachably connected to the second end of the optical fiber sensor chain; the two wings are symmetrically installed on the left and right sides of the guide shell, and the two wings are connected by a coupling; the tail wing is installed at the rear end of the guide shell; four propellers are installed on the guide shell and form a symmetrical structure; the electrical control module is respectively connected to the wave glider, the sonar obstacle avoidance module, the pressure depth module, the auxiliary sensor module, each wing, the tail wing and each propeller; the pressure depth module, the electrical control module and the auxiliary sensor module are located in the guide shell; The sonar obstacle avoidance module is used to detect in real time whether there is an obstacle in the moving direction of the towed body, and obtain obstacle information corresponding to the towed body when an obstacle is detected, and then generate an obstacle avoidance control instruction for the towed body based on the obstacle information; the electrical control module is used to control two wings, a tail wing and four propellers to perform obstacle avoidance operations based on the obstacle avoidance control instruction; The pressure depth module is used to obtain the depth information of the towed body in real time; the auxiliary sensor module is used to obtain the navigation information of the towed body and the environmental information corresponding to the towed body in real time; the electrical control module is also used to control two wings, a tail wing and four propellers to adjust the depth of the towed body based on preset depth information, the depth information, the navigation information and the environmental information.

2. The trailer control system according to claim 1, characterized in that: The obstacle information represents the relative position relationship between the obstacle and the towed body; the sonar obstacle avoidance module is also used to plan an obstacle avoidance path for the towed body based on the obstacle information, generate the obstacle avoidance control instruction based on the obstacle avoidance path, and then send the obstacle avoidance control instruction to the electrical control module.

3. The trailer control system according to claim 2, characterized in that: The obstacle information includes a first distance between the obstacle and the towed body; the sonar obstacle avoidance module includes a sonar detector installed on the top outer surface of the deflector shell and a data processing unit located in the deflector shell; the sonar detector is used to transmit a sound wave signal and receive an echo signal obtained after the obstacle reflects the sound wave signal when there is an obstacle on the transmission path of the sound wave signal; the data processing unit is used to determine the first distance based on the echo signal.

4. The trailer control system according to claim 3, characterized in that: The sonar obstacle avoidance module also includes a display unit and / or an alarm unit; the display unit is used to visually display the obstacle information when an obstacle is detected; the alarm unit is used to generate alarm information based on the obstacle information when an obstacle is detected, and to make an audible and visual alarm based on the alarm information.

5. The trailer control system according to claim 1, characterized in that: Two of the propellers are installed in pairs on the left side of the guide shell and are respectively located at the front and rear of the left side of the guide shell. The other two propellers are installed in pairs on the right side of the guide shell and are respectively located at the front and rear of the right side of the guide shell. The two propellers installed in pairs on the same side of the guide shell are symmetrically distributed front to back, the two propellers installed at the front of different sides of the guide shell are symmetrically distributed left to right, and the two propellers installed at the rear of different sides of the guide shell are symmetrically distributed left to right.

6. The trailer control system according to claim 1, characterized in that: The navigation information includes acceleration information, attitude information, heading information and position information of the towed body; the environmental information includes water flow velocity information of the surrounding environment of the towed body and the second distance between the towed body and the seabed; the auxiliary sensing module includes an accelerometer, a gyroscope, a magnetometer, a positioning sensor, an acoustic Doppler current meter, a laser rangefinder and a data fusion unit; the accelerometer is used to obtain the acceleration information in real time; the gyroscope is used to obtain the attitude information in real time; the magnetometer is used to obtain the heading information in real time; the positioning sensor is used to obtain the position information in real time; the acoustic Doppler current meter is used to obtain the water flow velocity information in real time; the laser rangefinder is used to obtain the second distance between the towed body and the seabed in real time; the data fusion unit is used to combine the navigation information and the environmental information into the environmental perception information of the towed body.

7. The trailer control system according to claim 6, characterized in that: The electrical control module is also used to determine a joint control strategy for the two wings and the four propellers based on the preset depth information and the environmental perception information, and control the two wings and the four propellers to adjust the depth of the towed body based on the joint control strategy; wherein the joint control strategy is used to adjust the rotation speed and direction of the four propellers using a dual closed-loop cascade PID control algorithm of angle and angular velocity, and adjust the angle of attack of the two wings and the thrust of the four propellers based on the preset depth information and the environmental perception information.

8. The trailer control system according to claim 3, characterized in that: The obstacle information also includes size information of the obstacle; and the data processing unit is further used to plan the obstacle avoidance path based on the first distance and the size information.

9. The trailer control system according to claim 1, characterized in that: The towing body also includes a fixing piece, which is detachably connected to the front end of the flow guide housing through an electromagnetic plug-in mechanism, and the fixing piece is fixedly connected to the second end of the optical fiber sensor chain.

10. A towing body control method for a wave glider, characterized in that: The towed body control method is applied to the towed body control system according to any one of claims 1 to 9, and the towed body control method comprises: The sonar obstacle avoidance module detects in real time whether there is an obstacle in the moving direction of the towed body, and obtains obstacle information corresponding to the towed body when an obstacle is detected, and then generates an obstacle avoidance control instruction for the towed body based on the obstacle information; The electrical control module controls two wings, a tail wing and four propellers to perform obstacle avoidance operations based on the obstacle avoidance control instruction; The pressure depth module acquires the depth information of the towed body in real time; The auxiliary sensing module acquires the navigation information of the towed body and the environmental information corresponding to the towed body in real time; The electrical control module controls two wings, a tail wing and four propellers to adjust the depth of the towed body based on preset depth information, the depth information, the navigation information and the environmental information.

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