System and method for autonomously adjusting attitude of suspended underwater docking platform

Abstract

The invention provides an autonomous attitude adjustment system and method for a suspended underwater docking platform. The autonomous attitude adjustment system comprises a buoyancy adjustment module, a power control module, a sensing module and an attitude control module, the buoyancy adjusting module is arranged on the butt joint platform, and the buoyancy adjusting module adjusts the buoyancy borne by the butt joint platform through water filling and drainage; the power control module is connected with the buoyancy adjusting module and used for controlling water filling and draining of the buoyancy adjusting module. The sensing module is used for collecting attitude data of the docking platform and adjusting data of the buoyancy adjusting module, and the attitude control module and the sensing module perform data interaction; the attitude control module controls the buoyancy adjusting module through the power control module according to data collected by the sensing module. The closed-loop feedback control system is utilized, the drainage volume of each buoyancy adjusting device arranged on the platform is changed according to the platform attitude deviation, the platform buoyancy is balanced, the optimal docking attitude is kept, and the docking task requirement of one or more aircrafts is met.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater unmanned docking of aircraft, and in particular to an autonomous attitude adjustment system and method for a suspended underwater docking platform. Background Art

[0002] With the continuous expansion of the depth and breadth of ocean development and utilization, autonomous underwater vehicles are widely used in various sea areas. They are a kind of marine unmanned navigation equipment with high practicality and broad prospects. However, due to the shortcomings of limited navigation distance and weak communication capabilities of the vehicles, they cannot perform long-term and continuous operations underwater, and need to be repeatedly deployed and recovered, resulting in low work efficiency. In order to overcome the above problems, the industry generally adopts underwater docking platforms to provide operational mission guarantees for the vehicles and meet their requirements such as energy replenishment and data relay transmission.

[0003] In order to more efficiently complete the scanning and detection tasks of terrain, landforms or marine life in a large area of ​​water, multiple aircraft are often used to carry out operations at the same time, so it is necessary to do a good job of docking and guaranteeing energy replenishment and data relay transmission for multiple aircraft at the same time. However, the docking efficiency of a single docking platform is low, and it can only meet the docking guarantee needs of a single aircraft at the same time, and cannot meet the efficient docking and recovery of multiple aircraft working at the same time. Therefore, relevant research has also been carried out on underwater docking platforms that can provide docking guarantees for multiple aircraft.

[0004] Common deployment methods for underwater docking platforms include floating deployment or bottom deployment. The former has a wider range of environmental adaptability than the latter and has lower requirements for ocean bottom and terrain. The floating underwater docking platform provides a stable docking guarantee environment for the aircraft, allowing the aircraft to efficiently charge and transmit data within the stable docking platform, while reducing the possibility of accidental impact damage to the exposed parts of the aircraft that have not entered the docking device and reducing the disturbance of the ocean current. The underwater docking platform will involve large-scale actions such as pushing out / retracting the docking device during the work process, and will retract all the aircraft after successful docking to the platform. In the suspended state, the above-mentioned push / retract actions will cause the platform's posture to change, which will not meet the requirements for aircraft docking and reduce the success rate of the docking mission. At the same time, the harsh and complex underwater environment will also affect the attitude and stability of the platform.

[0005] After reviewing existing patents and documents, it is found that the existing technologies for attitude adjustment of suspended docking platforms are mainly aimed at single docking devices, and the underwater equipment and platforms are mainly aimed at attitude buoyancy adjustment technologies for unmanned aircraft. No relevant technical research on autonomous attitude adjustment of underwater docking platforms for multiple aircraft docking has been found. Therefore, the present invention is a system and method for autonomous attitude adjustment of suspended underwater docking platforms and is of great importance.

[0006] The patent document with publication number CN206914586U discloses a buoyancy and attitude adjustable underwater device, including a device body, a sealing cylinder arranged beside the device body, the sealing cylinder having an opening, and the sealing cylinder including: a connecting disk that divides the sealing cylinder into two independent spaces; a push rod, the first end of which is connected to the connecting disk; a telescopic piston rod, the first end of which is connected to the second end of the push rod; a piston, the piston is connected to the second end of the telescopic piston rod; the piston, the connecting disk and the sealing cylinder form a sealed cavity. However, the patent document is different from the technical solution of the present application. Summary of the invention

[0007] In view of the defects in the prior art, the object of the present invention is to provide a system and method for autonomously adjusting the posture of a suspended underwater docking platform.

[0008] According to the present invention, a suspended underwater docking platform attitude autonomous adjustment system includes: a buoyancy adjustment module, a power control module, a perception module and an attitude control module;

[0009] The buoyancy adjustment module is arranged on the docking platform, and the buoyancy adjustment module adjusts the buoyancy of the docking platform by filling and discharging water;

[0010] The power control module is connected to the buoyancy regulating module and is used to control the filling and drainage of the buoyancy regulating module;

[0011] The perception module is used to collect the posture data of the docking platform and the adjustment data of the buoyancy adjustment module, and the posture control module exchanges data with the perception module;

[0012] The attitude control module controls the buoyancy adjustment module through the power control module according to the data collected by the perception module.

[0013] Preferably, the buoyancy adjustment module comprises: a filling and discharging mechanism, a piston cylinder and a piston;

[0014] The piston cylinder and the filling and drainage mechanism are arranged on a docking platform, the piston is arranged in the piston cylinder, and the piston can move in the piston cylinder;

[0015] The filling and drainage mechanism is drivingly connected to the piston via telescopic legs, and is used to drive the piston to move in the piston cylinder;

[0016] The sensing module is used to detect the displacement information of the telescopic legs on the filling and drainage mechanism;

[0017] The buoyancy regulating modules are provided in plurality, and the plurality of buoyancy regulating modules are respectively arranged at a plurality of azimuth angles of the docking platform.

[0018] Preferably, the perception module includes: a posture sensor and a displacement sensor;

[0019] The displacement sensor is arranged on the filling and drainage mechanism, and is used to collect displacement data of the telescopic legs on the filling and drainage mechanism, and transmit it to the posture control module as adjustment data;

[0020] The attitude sensor is installed at the geometric center of the docking platform, and is used to collect attitude data of the docking platform in real time, and transmit the collected attitude data to the attitude control module.

[0021] Preferably, the power control module comprises: a dry tank, a wet tank and a compensation oil bag;

[0022] The compensation oil bag is connected to the wet tank and is used to supply oil to the wet tank; the wet tank is provided with a hydraulic pump;

[0023] The dry cabin is connected to the wet cabin via a compartment sealing partition, and a control valve group is arranged in the dry cabin;

[0024] The wet tank is connected to the filling and drainage mechanism through the control valve group, and the posture control module realizes the connection and disconnection between the wet tank and the filling and drainage mechanism by controlling the opening and closing of the control valve group.

[0025] Preferably, a hydraulic control device and an AC drive motor are provided in the dry cabin;

[0026] The posture control module sends a control signal to the hydraulic control device, controls the AC drive motor through the hydraulic control device, and controls the opening and closing of the control valve group through the AC drive motor.

[0027] Preferably, the wet tank is connected to the compensation oil bag through an oil suction filter;

[0028] The control valve group is connected to the wet tank via a high-pressure filter;

[0029] The dry compartment is provided with an electrical interface and an oil circuit interface.

[0030] Preferably, the docking platform comprises: a main control cabin, a docking device, a push-out / retract mechanism, a buoy, an anchor, an anchor cable, a main frame and a platform frame;

[0031] The platform frame is arranged on the main frame, the buoyancy adjustment module is arranged on the main frame, and the power control module is arranged on the main frame;

[0032] The main control cabin, the docking device and the buoy are arranged on the main frame, and the push-out / retract mechanism is connected to the docking device;

[0033] The anchor is connected to the main frame via the anchor cable.

[0034] The present invention also provides a method for autonomously adjusting the attitude of a suspended underwater docking platform, based on the above-mentioned autonomous attitude adjustment system of the suspended underwater docking platform, comprising the following steps:

[0035] Step S1: receiving the posture data collected by the posture sensor of the collection and perception module in real time through the posture control module, and comparing the received posture data with the set posture data. When the posture deviation between the two does not meet the set requirements, the adjustment steps of step S2 and step S3 are performed;

[0036] Step S2: the posture data includes the pitch angle α and the roll angle β of the docking platform. According to the positive and negative values ​​of the pitch angle α and the roll angle β, the heights of the multiple azimuth angles of the docking platform are sorted. Based on the chasing leveling method, the piston cylinder that maintains the unchanged displacement volume is identified and used as the chasing target;

[0037] Step S3: Analyze the attitude deviation between each azimuth angle and the pursuit target through the attitude control module, analyze the filling and drainage requirements of the piston cylinder at each azimuth angle according to the attitude deviation, and convert it into the displacement of the filling and drainage mechanism at each azimuth angle, transmit the instruction to the power control module through the attitude control module, further decompose the instruction through the power control module, control the direction and opening of the electric proportional reversing valve of the control valve connected to each of the filling and drainage mechanisms in the control valve group, drive the piston up and down through the telescopic legs, adjust the piston cylinder at each azimuth angle to fill and drain, change the drainage volume, and adjust the buoyancy of the platform at all azimuth angles;

[0038] Step S4: Repeat steps S1 to S3 to continuously reduce the posture deviation until the posture deviation between the collected posture data and the set posture data is within the set range, thereby achieving posture adjustment.

[0039] Preferably, in step 2, in combination with the movement direction of the docking device, a piston cylinder that maintains a constant displacement volume is determined as a pursuit target;

[0040] When the docking device is inside the docking platform, the docking platform is in a balanced state;

[0041] When the docking device is pushed out of the docking platform by the push-out / retract mechanism, the docking platform tends to tilt forward, with the piston cylinder at the highest point as the target;

[0042] When the docking device is retracted into the docking platform by the push-out / retract mechanism, the docking platform tends to tilt backward, with the piston cylinder at the lowest point as the target.

[0043] Preferably, the buoyancy adjustment modules are provided at four azimuth angles of the docking platform;

[0044] The power control module changes the piston adjustment speed by changing the opening size of the electric proportional reversing valve of the charging and draining mechanism, setting the piston h at each azimuth angle. i The rate of change of the hydraulic oil flow Q through the electric proportional reversing valve i Proportional to:

[0045]

[0046] Where i = 1, 2, 3, 4; k i is the proportionality coefficient associated with the i-th filling and drainage mechanism, reflecting the effect of flow rate on the piston change rate per unit time;

[0047] Hydraulic oil flow rate Q i The opening u of the electric proportional reversing valve i Decide, assuming there is a linear relationship between the two:

[0048] Q i =c i u i

[0049] Among them, c i is the proportional coefficient related to the characteristics of the i-th electric proportional directional valve. In summary, piston h i The relationship between the rate of change and the opening of the electric proportional reversing valve:

[0050]

[0051] Piston h i Displacement H i With buoyancy F i The relationship between is linear, expressed as:

[0052] F i =εH i

[0053] Where ε is the proportionality coefficient related to the docking platform and buoyancy;

[0054] Calculate the required buoyancy F according to the pitch angle α and roll angle β of the docking platform's current attitude i , determine the opening u of each electric proportional reversing valve i , an adaptive control algorithm is used to achieve real-time adjustment of the dynamic characteristics of the system. The specific expression is as follows:

[0055] F f1 +F f2 +F f3 +Ff4 =W+T

[0056] F f1 y 1 +F f2 y 2 +F f3 y 3 +F f4 y 4 =0

[0057] F f1 x 1 +F f2 x 2 +F f3 x 3 +F f4 x 4 =0

[0058]

[0059] e x =α-α target

[0060] e y =β-β target

[0061]

[0062] Where W is the underwater net weight of the docking platform, L x , L y are the length and width of the platform, k and λ are adaptive parameters, ΔU is the control law, e is the attitude error, is the rate of change of error, F f1 、F f2 、F f3 、F f4 is the buoyancy change provided by the buoyancy adjustment module at each azimuth angle, T is the vertical component of the tension of the anchor cable on the docking platform, y 1 ,y 2 ,y 3 ,y 4 、x 1 、x 2 、x 3 、x 4 are respectively represented by the distances between the filling and drainage mechanisms and the geometric center point of the docking platform on the X-axis and the Y-axis, α target , β target They respectively represent the target values ​​of the pitch angle α and the roll angle β, and ex and ey respectively represent the difference between the real-time value and the target value of the pitch angle α and the roll angle β.

[0063] Compared with the prior art, the present invention has the following beneficial effects:

[0064] 1. The underwater docking platform attitude autonomous adjustment system of the present invention has the coordinated control function of buoyancy adjustment and docking actuator. By establishing a mathematical model of the piston displacement change rate and the opening of the electric proportional reversing valve corresponding to the buoyancy adjustment module, the relationship between each piston displacement and the buoyancy is determined, and the required buoyancy is calculated according to the horizontal attitude of the platform, and then the opening of each electric proportional reversing valve is determined. The adaptive control algorithm is further used to realize the autonomous adjustment of buoyancy, so as to control the platform to maintain the desired attitude.

[0065] 2. The underwater docking platform attitude autonomous adjustment system of the present invention is modularly designed, and has the characteristics of good flexibility, strong scalability and easy maintenance. Since the buoyancy adjustment module only needs to be flexibly connected to the power control module, the number and layout of the buoyancy adjustment module can be flexibly configured according to the operating characteristics of the underwater docking platform to change the platform buoyancy distribution and buoyancy adjustment range.

[0066] 3. The buoyancy adjustment module of the present invention is simple in composition and no longer uses an oil bladder to change the displacement volume. This can avoid the influence of the uncertain deformation of the flexible oil bladder in a complex underwater environment on the buoyancy adjustment control, and the size of the piston cylinder can be changed according to the buoyancy adjustment range requirements.

[0067] 4. The power control module of the present invention adopts a hydraulic system and an integrated design, which is easy to expand and can effectively reduce the weight and size of the docking platform. Through the closed and pressure compensation design, there is no material exchange with the outside world, which improves the anti-corrosion and anti-pollution capabilities, realizes reliable protection of non-pressure-resistant devices, and can adapt to deep underwater working environments.

[0068] 5. The present invention has wide applicability. The autonomous adjustment system and method are not only applicable to docking platforms for single or multiple vehicles, but also to attitude adjustment of other suspended underwater working platforms, which can meet the attitude requirements of the onboard equipment or the platform as a whole. At the same time, it can be used to meet the overall buoyancy adjustment of the platform within a certain range, improve the platform's adaptability to underwater environments, and have strong anti-interference capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0069] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0070] Figure 1 The present invention is a schematic diagram of an autonomous attitude adjustment system for an underwater docking platform.

[0071] Figure 2 It is a schematic diagram of a buoyancy adjustment module involved in the present invention.

[0072] Figure 3 It is a schematic diagram of a power control module involved in the present invention.

[0073] Figure 4 It is a schematic diagram of a docking device of a suspended underwater docking platform involved in the present invention being retracted into the platform.

[0074] Figure 5 The present invention is a schematic diagram of posture changes caused when a docking device of a suspended underwater docking platform is pushed out of the platform.

[0075] Figure 6 The present invention relates to an underwater docking platform.

[0076] Figure 7 It is a logic flow chart of the present invention for realizing autonomous posture adjustment and buoyancy adjustment.

[0077] Figure 8 The utility model is a schematic diagram of a hydraulic system involved in the present invention.

[0078] The figure shows:

[0079] Buoyancy adjustment module 1 Compensation oil bag 17

[0080] Power control module 2 compartment sealing partition 18

[0081] Sensing module 3 Hydraulic control device 19

[0082] Attitude control module 4 AC drive motor 20

[0083] Main frame 5 High pressure filter 21

[0084] Main control cabin 6 control valve group 22

[0085] Filling and draining mechanism 7 Hydraulic pump 23

[0086] Piston cylinder 8 Oil suction filter 24

[0087] Piston 9 Electrical interface 25

[0088] Platform frame 10 Oil circuit interface 26

[0089] Telescopic legs 11 Docking device 27

[0090] Attitude sensor 12 Float 28

[0091] Displacement sensor 13 Anchor 29

[0092] Push out / retract mechanism 14 Anchor cable 30

[0093] Dry tank 15 Aircraft 31

[0094] Wet Tank 16 DETAILED DESCRIPTION

[0095] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0096] Embodiment 1:

[0097] like Figure 1-8 As shown, this embodiment provides a suspended underwater docking platform posture autonomous adjustment system, including: a buoyancy adjustment module 1, a power control module 2, a perception module 3 and a posture control module 4; the buoyancy adjustment module 1 is arranged on the docking platform, and the buoyancy adjustment module 1 adjusts the buoyancy of the docking platform by filling and discharging water; the power control module 2 is connected to the buoyancy adjustment module 1, and is used to control the filling and discharging of the buoyancy adjustment module 1; the perception module 3 is used to collect the posture data of the docking platform and the adjustment data of the buoyancy adjustment module 1, and the posture control module 4 exchanges data with the perception module 3; the posture control module 4 controls the buoyancy adjustment module 1 through the power control module 2 according to the data collected by the perception module 3.

[0098] The docking platform includes: a main control cabin 6, a docking device 27, a push-out / retract mechanism 14, a buoy 28, an anchor 29, an anchor cable 30, a main frame 5 and a platform frame 10; the platform frame 10 is arranged on the main frame 5, the buoyancy adjustment module 1 is arranged on the main frame 5, and the power control module 2 is arranged on the main frame 5; the main control cabin 6, the docking device 27 and the buoy 28 are arranged on the main frame 5, and the push-out / retract mechanism 14 is connected to the docking device 27; the anchor 29 is connected to the main frame 5 through the anchor cable 30.

[0099] The perception module 3 includes: a posture sensor 12 and a displacement sensor 13; the displacement sensor 13 is arranged on the filling and drainage mechanism 7, and is used to collect the displacement data of the telescopic legs 11 on the filling and drainage mechanism 7, and transmit it to the posture control module 4 as adjustment data; the posture sensor 12 is installed at the geometric center of the docking platform, and is used to collect the posture data of the docking platform in real time, and transmit the collected posture data to the posture control module 4.

[0100] The buoyancy adjustment module 1 includes: a charging and discharging mechanism 7, a piston cylinder 8 and a piston 9; the piston cylinder 8 and the charging and discharging mechanism 7 are arranged on the docking platform, the piston 9 is arranged in the piston cylinder 8, and the piston 9 can move in the piston cylinder 8; the charging and discharging mechanism 7 is connected to the piston 9 through the telescopic legs 11, which is used to drive the piston 9 to move in the piston cylinder 8; the sensing module 3 is used to detect the displacement information of the telescopic legs 11 on the charging and discharging mechanism 7; the buoyancy adjustment module 1 is set to multiple, and the multiple buoyancy adjustment modules 1 are respectively arranged at multiple azimuths of the docking platform.

[0101] The power control module 2 includes: a dry tank 15, a wet tank 16 and a compensation oil bag 17; the compensation oil bag 17 is connected to the wet tank 16 and is used to supply oil to the wet tank 16; the wet tank 16 is provided with a hydraulic pump 23; the dry tank 15 is connected to the wet tank 16 through a compartment sealing partition 18, and a control valve group 22 is provided in the dry tank 15; the wet tank 16 is connected to the charging and drainage mechanism 7 through the control valve group 22, and the attitude control module 4 realizes the connection and disconnection between the wet tank 16 and the charging and drainage mechanism 7 by controlling the opening and closing of the control valve group 22. A hydraulic control device 19 and an AC drive motor 20 are provided in the dry tank 15; the attitude control module 4 sends a control signal to the hydraulic control device 19, controls the AC drive motor 20 through the hydraulic control device 19, and controls the opening and closing of the control valve group 22 through the AC drive motor 20. The wet tank 16 is connected to the compensation oil bag 17 through the oil suction filter 24; the control valve group 22 is connected to the wet tank 16 through the high-pressure filter 21; the dry tank 15 is provided with an electrical interface 25 and an oil circuit interface 26.

[0102] This embodiment also provides a method for autonomously adjusting the attitude of a suspended underwater docking platform, based on the above-mentioned autonomous attitude adjustment system of a suspended underwater docking platform, comprising the following steps:

[0103] Step S1: receiving the posture data collected by the posture sensor 12 of the collection perception module 3 in real time through the posture control module 4, and comparing the received posture data with the set posture data. When the posture deviation between the two does not meet the set requirements, the adjustment steps of step S2 and step S3 are performed;

[0104] Step S2: the posture data includes the pitch angle α and the roll angle β of the docking platform. According to the positive and negative values ​​of the pitch angle α and the roll angle β, the heights of the multiple azimuth angles of the docking platform are sorted. Based on the chasing leveling method, the piston cylinder 8 that maintains the unchanged displacement volume is confirmed and taken as the chasing target;

[0105] In combination with the movement direction of the docking device 27, the piston cylinder 8 which keeps the displacement volume unchanged is determined as the pursuit target;

[0106] When the docking device 27 is inside the docking platform, the docking platform is in a balanced state;

[0107] When the docking device 27 is pushed out of the docking platform by the push-out / retract mechanism 4, the docking platform tends to tilt forward, with the piston cylinder 8 at the highest point as the target;

[0108] When the docking device 27 is retracted into the docking platform by the push-out / retract mechanism 4, the docking platform tends to tilt backward, with the piston cylinder 8 at the lowest point as the target;

[0109] After the piston cylinder 8 as the pursuit target is determined, the buoyancy of the positions of the remaining piston cylinders 8 is adjusted by adjusting the filling and drainage mechanisms 7 connected to the remaining piston cylinders 8, thereby adjusting the posture of the docking platform.

[0110] Step S3: Analyze the attitude deviation between each azimuth angle and the target being pursued through the attitude control module 4, analyze the filling and drainage requirements of the piston cylinder 8 at each azimuth angle according to the attitude deviation, and convert it into the displacement of the filling and drainage mechanism 7 at each azimuth angle, transmit the instruction to the power control module 2 through the attitude control module 4, and further decompose the instruction through the power control module 2 to control the direction and opening of the electric proportional reversing valve of the control valve connected to each filling and drainage mechanism 7 in the control valve group, drive the piston 9 up and down through the telescopic legs 11, adjust the piston cylinder 8 at each azimuth angle to fill and drain, change the drainage volume, and adjust the buoyancy of the platform at each azimuth angle;

[0111] Step S4: Repeat steps S1 to S3 to continuously reduce the posture deviation until the posture deviation between the collected posture data and the set posture data is within the set range, thereby achieving posture adjustment.

[0112] Buoyancy adjustment modules 1 are provided at four azimuth angles of the docking platform;

[0113] The power control module 2 changes the piston adjustment speed by changing the opening size of the electric proportional reversing valve of the charging and draining mechanism 7, setting the piston h at each azimuth angle. i The rate of change of the hydraulic oil flow Q through the electric proportional reversing valve i Proportional to:

[0114]

[0115] Where i = 1, 2, 3, 4; k i is the proportionality coefficient associated with the i-th filling and drainage mechanism 7, reflecting the effect of the flow rate on the piston change rate per unit time;

[0116] Hydraulic oil flow rate Q i The opening u of the electric proportional reversing valve i Decide, assuming there is a linear relationship between the two:

[0117] Q i =c i u i

[0118] Among them, c i is the proportional coefficient related to the characteristics of the i-th electric proportional directional valve. In summary, piston h i The relationship between the rate of change and the opening of the electric proportional reversing valve:

[0119]

[0120] Piston h i Displacement H i With buoyancy F i The relationship between is linear, expressed as:

[0121] F i =εH i

[0122] Where ε is the proportionality coefficient related to the docking platform and buoyancy;

[0123] Calculate the required buoyancy F according to the pitch angle α and roll angle β of the docking platform's current attitude i , determine the opening u of each electric proportional directional valve i , an adaptive control algorithm is used to achieve real-time adjustment of the dynamic characteristics of the system. The specific expression is as follows:

[0124] F f1 +F f2 +F f3 +F f4 =W+T

[0125] F f1 y 1 +F f2 y 2 +F f3 y 3 +F f4 y 4 =0

[0126] F f1 x 1 +F f2 x 2 +F f3 x 3 +F f4 x 4 =0

[0127]

[0128] e x =α-α target

[0129] e y =β-β target

[0130]

[0131] Where W is the underwater net weight of the docking platform, L x , L y are the length and width of the platform, k and λ are adaptive parameters, ΔU is the control law, e is the attitude error, is the rate of change of error, F f1 、F f2 、F f3 、F f4 is the buoyancy change provided by the buoyancy adjustment module 1 at each azimuth angle, T is the vertical component of the tension of the anchor cable 30 on the docking platform, y 1 ,y 2 ,y 3 ,y 4 、x 1 、x 2 、x 3 、x 4 They are respectively represented by the X-axis and Y-axis distances between each filling and drainage mechanism and the geometric center point of the docking platform, α target , β target They represent the target values ​​of the pitch angle α and the roll angle β respectively, and ex and ey represent the difference between the real-time value and the target value of the pitch angle α and the roll angle β respectively, that is, the attitude error.

[0132] In order to solve the problem of adjusting the platform attitude of an underwater docking platform with multiple vehicles docked when performing work tasks or in harsh underwater environments, the present embodiment provides a system and method for autonomously adjusting the attitude of a suspended underwater docking platform. The attitude of the underwater docking platform in a suspended state is controlled through buoyancy control. Specifically, a closed-loop feedback control system is used to change the displacement volume of each buoyancy adjustment device arranged on the platform according to the platform attitude deviation, so as to balance the platform buoyancy and maintain the optimal docking attitude to meet the docking task requirements of a single or multiple vehicles. The system can also be applied to the attitude adjustment of other suspended underwater working platforms to meet their working attitude requirements. The system has good flexibility and wide applicability.

[0133] The adjustment system of this embodiment has good flexibility. The autonomous adjustment system and method are modularly designed. The buoyancy adjustment module can be arranged in various places on the platform according to the changes in the platform's posture before and after operation. It only needs to be connected to the power control module with pipelines to adjust the buoyancy distribution of the platform, and can be flexibly arranged. The buoyancy adjustment module no longer uses an oil bag to change the displacement volume, but directly relies on the reciprocating motion of the piston to change the displacement volume of the system, which can avoid the influence of the uncertain deformation of the flexible oil bag in a complex underwater environment on the buoyancy adjustment control.

[0134] The adjustment system of this embodiment is highly compact, and the power control module can meet the needs of an underwater working platform with distributed and multi-drive characteristics, thereby improving the compactness of the platform. Through a fully enclosed integrated design, it has the advantages of corrosion resistance, compensation system pressure, and strong environmental adaptability.

[0135] Embodiment 2:

[0136] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0137] The present embodiment provides an autonomous attitude adjustment system for a suspended underwater docking platform, including a buoyancy adjustment module, a power control module, a sensing module and an attitude control module.

[0138] The buoyancy adjustment module includes a filling and drainage mechanism, a piston cylinder, and a piston. The piston cylinder is fixedly installed above the platform. The number, size, and installation position of the piston cylinder can be determined according to the size, layout, and buoyancy adjustment range of the docking platform. Generally, it is arranged at the four corners of the platform, at least four, and an additional piston cylinder is provided when the attitude stability of the docking platform and the maximum adjustment capacity of the system need to be increased. The filling and drainage mechanism is installed on one side of the piston cylinder and is rigidly connected to the piston. The piston and the circumferential surface of the piston cylinder are reliably sealed. The piston can slide back and forth in the piston cylinder under the drive of the filling and drainage mechanism to change the drainage volume. When the actuator is extended, that is, close to the outlet side of the piston cylinder, the drainage volume increases and the buoyancy increases. On the contrary, the drainage volume decreases and the buoyancy decreases. The buoyancy of the docking platform where the buoyancy adjustment module is arranged can be adjusted, so that the total buoyancy center can change in space, adapt to the change of the center of gravity when the docking platform pushes out / retracts the docking device, and then adjust the platform attitude. When the underwater environment changes and the disturbance increases, the buoyancy adjustment module can further improve the anti-flow capacity by increasing the buoyancy of the platform as a whole.

[0139] The power control module includes a hydraulic pump, a filter, a control valve group, a pressure compensation device, a pressure sensor, etc., which serve as the power of the system, control the direction and size of the filling and drainage mechanism, adjust the drainage volume of the buoyancy adjustment module at each location, and change the buoyancy size. The power control module can also meet the distributed and multi-drive characteristics of multiple aircraft docking underwater docking platforms. The power control module adopts a hydraulic system approach, with an integrated design, which is easy to expand and can effectively reduce the weight and size of the docking platform. It provides a power source for the buoyancy adjustment module and other functional actuators of the multiple aircraft docking underwater docking platform, realizes the buoyancy adjustment function and the linkage capability of the distributed actuator, and has the collaborative control function of multiple actuators. The module has a closed and pressure-compensated design, has no material exchange with the outside world, improves the anti-corrosion and anti-pollution capabilities, realizes reliable protection of non-pressure-resistant devices, and can adapt to deep underwater operating environments.

[0140] The sensing module includes a posture sensor and displacement sensors of each charging and discharging mechanism. The posture sensor is installed at the geometric center of the platform to collect platform posture information in real time and serve as monitoring and control parameters of the posture control module feedback system. The displacement sensors of each actuator are installed on the telescopic legs of the actuator. The displacement volume of each buoyancy adjustment module is obtained according to the specific values ​​of the displacement sensor, which is conducive to buoyancy adjustment control.

[0141] The attitude control module is packaged or integrated in the main control cabin of the underwater docking platform, interacts with the perception module, collects the platform attitude information in real time, and is connected to the power control module control. In combination with the adaptive control algorithm, according to the attitude data deviation and the displacement stroke of each charging and discharging mechanism, a fixed point is determined as the "chasing" target, the target is kept unchanged, and the action of the charging and discharging mechanism is controlled through closed-loop feedback control to continuously reduce the attitude deviation and realize attitude adjustment. Specifically, the attitude control module analyzes the height order of each position of the platform according to the positive and negative directions and numerical values ​​of the pitch angle α and the roll angle β given by the attitude sensor, and determines the chasing target point in combination with the action of the push / retract device. The displacement volume of the piston cylinder at the target point remains unchanged, that is, the buoyancy remains unchanged, and the buoyancy adjustment strategies of other piston cylinders in the buoyancy adjustment module are analyzed and calculated, and the adjustment instructions are issued to the power control module, the direction and opening of the electric proportional reversing valve corresponding to each charging and discharging mechanism are changed, and the flow of hydraulic oil is further adjusted to adjust the position of the piston in the piston cylinder, and the charging and discharging is performed, and the displacement volume of other piston cylinders is continuously adjusted, the buoyancy size is changed, the buoyancy of different parts of the platform is balanced, and the platform attitude is adjusted autonomously.

[0142] This embodiment provides an autonomous adjustment system for the posture of a suspended underwater docking platform, and also proposes an autonomous adjustment method. The method can be applied to other underwater suspended working platforms. The autonomous adjustment of the platform posture can improve the measurement accuracy of the instruments and equipment on the platform.

[0143] This embodiment brings the following beneficial effects:

[0144] a. Wide applicability: The autonomous adjustment system and method of this embodiment is not only applicable to docking platforms for single or multiple vehicles, but also to attitude adjustment of other suspended underwater working platforms, which can meet the attitude requirements of the equipment or the platform as a whole. At the same time, it is used to meet the overall buoyancy adjustment of the platform within a certain range, improve the platform's ability to adapt to the underwater environment, and have strong anti-interference ability.

[0145] b. Good flexibility. The autonomous adjustment system and method of this embodiment is modularly designed. The buoyancy adjustment module can be arranged at various places on the platform according to the changes in the platform's posture before and after operation. It only needs to be connected to the power control module with pipelines to adjust the buoyancy distribution of the platform, which can be flexibly arranged. In addition, the buoyancy adjustment module no longer uses an oil bag to change the displacement volume, but directly relies on the reciprocating motion of the piston to change the displacement volume of the system, which can avoid the influence of the uncertain deformation of the flexible oil bag in a complex underwater environment on the buoyancy adjustment control.

[0146] c. High compactness. The power control module of this embodiment can meet the needs of an underwater working platform with distributed and multi-drive characteristics, improve the compactness of the platform, and through a fully enclosed integrated design, it has the advantages of corrosion resistance, compensation system pressure, etc., and has strong environmental adaptability.

[0147] Embodiment 3:

[0148] Those skilled in the art may understand this embodiment as a more specific description of Embodiment 1.

[0149] This embodiment takes a docking platform with two docking devices as an example to explain in detail a system and method for autonomous posture adjustment of a suspended underwater docking platform.

[0150] like Figure 1 ,like Figure 2 As shown, the system mainly includes a buoyancy adjustment module 1, a power control module 2, a sensing module 3 and a posture control module 4, and the system is arranged in the main frame 5 of the docking platform. The posture control module 4 is integrated and installed in the main control cabin 6 of the docking platform. The main control cabin 6 is fixedly installed in the lower middle front part of the platform, receives the superior task instructions and issues the action instructions of each actuator to the power control module 2. The buoyancy adjustment module 1 includes a filling and drainage mechanism 7, a piston cylinder 8, and a piston 9. The piston cylinder 8 is installed at the upper four corners of the docking platform, and the piston cylinder 8 is fixedly installed on the platform frame 10. The filling and drainage mechanism 7 is vertically fixed on the platform frame 10 at the bottom of the platform. The telescopic legs 11 of the filling and drainage mechanism 7 are rigidly connected to the piston 9. The telescopic legs 11 are extended and retracted to drive the piston 9 to move up and down along the piston cylinder wall, change the displacement volume of the piston cylinder 8, and change the buoyancy provided at the piston cylinder 8. The sensing module 3 includes a posture sensor 12 arranged at the geometric center of the platform, the posture sensor 12 is a MEMS inertial navigation system, which is used to monitor and feedback the posture information of the platform, and a displacement sensor 13 installed on the filling and drainage mechanism 7, which can obtain the drainage volume of the piston cylinder according to the displacement sensor value.

[0151] like Figure 3As shown, the power control module 2 is an integrated dry and wet tank integrated design, which is the power source of the docking platform and the autonomous adjustment system, and provides power for each actuator, including the filling and drainage mechanism 7 and the actuators of the docking platform to realize the docking function, such as the push-out / retract mechanism 14, etc., which are installed directly behind the main control cabin 6. The power control module 2 is mainly composed of a dry tank 15, a wet tank 16, and a compensation oil bag 17. The dry tank 15 and the wet tank 16 are separated by a compartment sealing partition 18. The dry tank 15 is filled with normal pressure air, and is equipped with hydraulic control devices 19, AC drive motors 20, high-pressure filters 21, control valve groups 22 and pressure sensors; the wet tank 16 is also used as an oil tank, which is filled with hydraulic oil and is equipped with hydraulic pumps 23, oil suction filters 24, temperature sensors and liquid level gauges; the compensation oil bag 17 is directly connected to the wet tank 16, which can keep the internal and external pressures of the wet tank 16 balanced, adapt to the deep working environment, and can also be used as a supplementary source of oil in the oil tank. An electrical interface 25 and an oil circuit interface 26 are arranged on the end cover of one side of the dry tank 15. The electrical interface 25 mainly includes an AC power supply interface for the motor, a DC power supply interface for the valve group and the sensor, and a control signal interface; the oil circuit interface 26 mainly includes two-way interfaces for the charging and drainage mechanism 7 and other distributed drive actuators of the docking platform, all of which use quick connectors for easy disassembly and assembly.

[0152] like Figure 4 As shown, the underwater docking platform of this embodiment includes a main control cabin 6, two docking devices 27, two push-out / retract mechanisms 14, a buoy 28, an anchor 29, an anchor cable 30, a main frame 5 and a platform frame 10. The docking devices 27 are distributed on both sides of the platform and are rigidly connected to the push-out / retract mechanism 14. Through the reciprocating linear motion of the push-out / retract mechanism 14, the docking device 27 pushes the platform to perform the docking task of the aircraft, and retracts the platform to charge the aircraft and transmit data; the buoy 28 is used to balance the buoyancy of the platform; the anchor 29 and the anchor cable 30 are used for anchoring and fixing the platform underwater; the main frame 5 and the platform frame 10 serve as the structural support of the docking platform and the installation and fixing frame of other components.

[0153] Figure 4 As shown, the docking device on the right side of the docking platform has completed the docking task, the aircraft 31 is in the charging and (or data transmission state, and the docking device on the left side is still in the waiting state for the docking task. After the docking platform receives the docking task, the push-out / retract mechanism 14 is activated to extend the docking device 27 out of the docking platform. This process will cause the platform posture to tilt, as shown in FIG. Figure 5 At this time, the MEMS inertial navigation transmits the attitude data to the attitude control module 4, and the attitude control module 4 autonomously adjusts the platform attitude according to the attitude deviation.

[0154] Assume that the left front of the docking platform is position 1, the right front is position 2, the left rear is position 3, and the right rear is position 4. Figure 6 As shown, initially, the pistons 9 in the piston cylinders 8 in the four directions are all in the middle position in the piston cylinder 8, which serves as the displacement volume when the platform is launched into the water. The specific process of the attitude autonomous adjustment is as follows:

[0155] Step 1: The attitude control module 4 collects the MEMS inertial navigation data of the perception module 3 in real time and compares it with the set attitude data. When it is found that the attitude deviation does not meet the set requirements, the autonomous adjustment program is started.

[0156] Step 2, sort the heights of platforms 1, 2, 3, and 4 according to the positive and negative values ​​of the pitch angle α and the roll angle β, and at the same time, combined with the action of the push / retract mechanism 14, determine the piston cylinder 8 that maintains the displacement volume unchanged and use it as the pursuit target.

[0157] The "chasing" leveling method is adopted. When the docking device 27 is in the process of being pushed out, the highest point piston cylinder 8 is the chasing target. When the docking device 27 is in the process of being retracted, the lowest point piston cylinder 8 is the chasing target, so as to keep its displacement volume unchanged.

[0158] Combined with the movement direction of the docking device 27, the piston cylinder 8 that keeps the displacement volume unchanged is determined, that is, the pursuit target. It can be seen that when the docking device 27 is inside the platform, the platform is in a balanced state. When the docking device 27 is pushed out by the push-out / retract mechanism 14, the platform tends to tilt forward, with the highest point as the pursuit target; when the docking device 27 is retracted by the push-out / retract mechanism 14, the platform tends to tilt backward, with the lowest point as the pursuit target. The remaining filling and drainage mechanisms adjust the buoyancy of the position and adjust the platform posture.

[0159] Step 3, according to the deviation between each azimuth angle and the pursuit target, analyze the filling and drainage requirements of the piston cylinder 8 in each azimuth, and convert it into the displacement of each filling and drainage mechanism 7, and transmit the command to the power control module 2. The power control module 2 further decomposes the command, controls the direction and opening of the electric proportional reversing valve of each filling and drainage mechanism 7, and the telescopic legs 11 drive the piston 9 to move up and down, adjusts each piston cylinder 8 for filling and drainage, changes the drainage volume, and adjusts the buoyancy of the platform in each azimuth.

[0160] Furthermore, the power control module 2 changes the piston adjustment speed by changing the opening size of the electric proportional reversing valve of the charging and draining mechanism 7, setting the piston h i The rate of change of (i=1,2,3,4) and the hydraulic oil flow Q through the electric proportional reversing valve i Proportional to:

[0161]

[0162] Among them, k iIt is the proportional coefficient related to the i-th filling and drainage mechanism, reflecting the influence of flow rate on the piston change rate per unit time.

[0163] Hydraulic oil flow rate Q i The opening u of the electric proportional reversing valve i Decision, we can assume that there is a linear relationship between the two:

[0164] Q i =c i u i (2)

[0165] Among them, c i is the proportional coefficient related to the characteristics of the i-th electric proportional directional valve. In summary, piston h i The relationship between the rate of change and the opening of the electric proportional reversing valve:

[0166]

[0167] Further, the piston h i Displacement H i With buoyancy F i The relationship between is linear and can be expressed as:

[0168] F i =εH i (4)

[0169] where ε is the proportionality factor related to the platform buoyancy.

[0170] Step 4: Repeat steps 1 to 3 to continuously reduce the attitude deviation until the deviation between the collected attitude data and the set attitude is within the set range to achieve attitude adjustment. Specifically, the required buoyancy F can be calculated based on the current attitude α, β of the platform. i , and then determine the opening u of each electric proportional reversing valve i In order to improve the control performance, an adaptive control algorithm is used to achieve real-time adjustment of the dynamic characteristics of the system to cope with uncertainty and changes. The specific expression is as follows:

[0171]

[0172] Where W is the net weight of the platform underwater, L x , L y are the length and width of the platform respectively, k and λ are adaptive parameters, ΔU is the control law, e is the attitude error, is the rate of change of error, F f1 、F f2 、F f3 、F f4 is the buoyancy change provided by each buoyancy regulating module, and T is the vertical component of the tension of the anchor cable 30.

[0173] The above-mentioned attitude autonomous adjustment process is also applicable to attitude change adjustment caused by external environment changes, and can also be used to adjust the overall buoyancy value of the docking platform to improve the anti-interference ability of the docking platform. The logic flow chart of this embodiment to achieve attitude autonomous adjustment and buoyancy adjustment is as follows: Figure 7 shown.

[0174] The hydraulic system schematic diagram of this embodiment is as follows: Figure 8 As shown, the system adopts a pressure compensation design, and senses the seawater pressure through the elastic element compensation oil bag 17, and transmits it to the inside of the hydraulic system, so that the return oil pressure of the hydraulic system is equal to the seawater pressure, and changes automatically with the change of the seawater depth. This method can eliminate the influence of water pressure during the execution process of the hydraulic cylinder of each actuator, reduce the use pressure of the cylinder, and reduce the power and space volume of the entire power control module 2, making the entire power system more concise and lightweight. A three-position four-way proportional reversing valve is used to realize the telescopic movement of each actuator, and the valve core opening is driven by the input PWM signal to complete the adjustment of the inlet and return oil flow, thereby controlling the operating rate of the mechanical actuator end; the middle function can be selected as Y type, that is, when the three-position four-way proportional reversing valve is in the middle position, the oil inlet P is closed, and the working oil ports A and B are connected to the return oil port T. The function of this locking circuit is to enable the hydraulic cylinder of the actuator to stay at any position, and after staying, it will not move due to external force; and the Y-type neutral position function is adopted to make the hydraulic system float, which can effectively reduce the adverse effects of the inertial load generated during the operation of the mechanical equipment. Finally, six groups of hydraulic control balance valves are used, and the control oil ports of each group are interconnected to form six groups of hydraulic locks to maintain the pressure of the entire actuator.

[0175] This embodiment is a suspended underwater docking platform posture autonomous adjustment system and method. The working process is as follows:

[0176] The docking platform is suspended in an underwater environment at a certain depth through the anchor 29 and the anchor cable 30. The attitude control module 4 calculates the change in the displacement volume of each piston cylinder 8 according to the attitude feedback data analysis, and the power control module 2 issues an adjustment command to autonomously adjust the platform attitude so that the platform adapts to the surrounding environmental water flow and maintains a stable attitude. The attitude control module 4 can synchronously adjust the displacement volume of each piston cylinder 8 according to the command to increase or decrease the total buoyancy of the platform.

[0177] When the platform receives one or more docking task instructions, each push-out / retract mechanism 14 is activated. During the process of the docking device 27 extending from the platform, the attitude control module 4 determines the pursuit target according to the attitude data deviation and the action instruction of the push-out / retract mechanism 14, and transmits the buoyancy adjustment instruction to the power control module 2. The power control module 2 controls each control valve group according to the instruction, controls the action of the charging and discharging mechanism 7, adjusts the buoyancy distribution of the platform, balances the change of the center of gravity of the platform, achieves autonomous adjustment of the platform, meets the requirements of the docking for the platform attitude, and improves the docking success rate.

[0178] When the platform completes the docking task, the push-out / retract mechanism 14 operates to retract the docking device 27 and the docked aircraft into the platform to prevent the tail of the aircraft from being accidentally hit or affected by other environmental disturbances, maintain the stability of the platform in the water, and ensure that the successfully docked aircraft has more efficient charging and (or) data transmission efficiency. The process adjustment procedure is the same as above, and the attitude autonomous adjustment system autonomously adjusts the attitude of the platform to ensure the attitude stability of the platform.

[0179] The underwater docking platform attitude autonomous adjustment system has the function of coordinated control of buoyancy adjustment and docking actuator. By establishing a mathematical model of the piston displacement change rate and the opening of the electric proportional reversing valve corresponding to the buoyancy adjustment module, the relationship between each piston displacement and buoyancy is determined, and the required buoyancy is calculated according to the horizontal attitude of the platform, and then the opening of each electric proportional reversing valve is determined. The adaptive control algorithm is further used to realize autonomous adjustment of buoyancy, so as to control the platform to maintain the desired attitude.

[0180] The underwater docking platform attitude autonomous adjustment system is modularly designed, with good flexibility, strong scalability and easy maintenance. The buoyancy adjustment module can be flexibly configured in number and layout according to the operation characteristics of the underwater docking platform to change the platform buoyancy distribution and buoyancy adjustment range because it is only connected to the power control module through a flexible connection.

[0181] The buoyancy adjustment module is simple in composition and no longer uses an oil bladder to change the displacement volume, which can avoid the influence of the uncertain deformation of the flexible oil bladder in a complex underwater environment on the buoyancy adjustment control, and the size of the piston cylinder can be changed according to the buoyancy adjustment range requirements.

[0182] The power control module adopts a hydraulic system and an integrated design, which is easy to expand and can effectively reduce the weight and size of the docking platform. Through the closed and pressure compensation design, there is no material exchange with the outside world, which improves the anti-corrosion and anti-pollution capabilities, realizes reliable protection of non-pressure-resistant components, and can adapt to deep underwater operating environments.

[0183] To sum up, the above are only preferred embodiments of the present invention. Changes in the number of integrated docking devices, the number and layout of buoyancy adjustment modules included in the underwater docking platform all fall within the scope of patent protection of the present invention. The autonomous attitude adjustment system and method described in the present invention are also applicable to other underwater working platforms, and their application in related platforms should also fall within the scope of patent protection of the present invention.

[0184] The present invention utilizes a closed-loop feedback control system to change the displacement volume of each buoyancy regulating device arranged on the platform according to the platform attitude deviation, balance the platform buoyancy to maintain the best docking attitude, and meet the docking mission requirements of single or multiple vehicles.

[0185] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0186] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A suspended underwater docking platform attitude autonomous adjustment system, characterized in that: include: A buoyancy adjustment module (1), a power control module (2), a perception module (3) and a posture control module (4); The buoyancy adjustment module (1) is arranged on the docking platform, and the buoyancy adjustment module (1) adjusts the buoyancy exerted on the docking platform by filling and discharging water; The power control module (2) is connected to the buoyancy regulating module (1) and is used to control the filling and drainage of the buoyancy regulating module (1); The perception module (3) is used to collect the posture data of the docking platform and the adjustment data of the buoyancy adjustment module (1), and the posture control module (4) performs data exchange with the perception module (3); The posture control module (4) controls the buoyancy adjustment module (1) through the power control module (2) based on the data collected by the perception module (3).

2. The self-adjusting system for the suspended underwater docking platform according to claim 1 is characterized in that: The buoyancy adjustment module (1) comprises: a filling and drainage mechanism (7), a piston cylinder (8) and a piston (9); The piston cylinder (8) and the filling and drainage mechanism (7) are arranged on a docking platform, the piston (9) is arranged in the piston cylinder (8), and the piston (9) can move in the piston cylinder (8); The filling and drainage mechanism (7) is drivingly connected to the piston (9) via a telescopic leg (11) and is used to drive the piston (9) to move in the piston cylinder (8); The sensing module (3) is used to detect the displacement information of the telescopic legs (11) on the filling and drainage mechanism (7); The buoyancy adjustment module (1) is arranged in plurality, and the plurality of buoyancy adjustment modules (1) are respectively arranged at a plurality of azimuth angles of the docking platform.

3. The self-adjusting system for the suspended underwater docking platform according to claim 2 is characterized in that: The sensing module (3) comprises: a posture sensor (12) and a displacement sensor (13); The displacement sensor (13) is arranged on the filling and drainage mechanism (7) and is used to collect displacement data of the telescopic legs (11) on the filling and drainage mechanism (7) and transmit the displacement data to the posture control module (4) as adjustment data; The attitude sensor (12) is installed at the geometric center of the docking platform and is used to collect attitude data of the docking platform in real time and transmit the collected attitude data to the attitude control module (4).

4. The self-adjusting system for the suspended underwater docking platform according to claim 3 is characterized in that: The power control module (2) comprises: a dry compartment (15), a wet compartment (16) and a compensation oil bag (17); The compensation oil bag (17) is connected to the wet tank (16) and is used to supply oil to the wet tank (16); the wet tank (16) is provided with a hydraulic pump (23); The dry tank (15) is connected to the wet tank (16) via a compartment sealing partition (18), and a control valve group (22) is arranged in the dry tank (15); The wet tank (16) is connected to the filling and drainage mechanism (7) via the control valve group (22), and the posture control module (4) realizes connection and disconnection between the wet tank (16) and the filling and drainage mechanism (7) by controlling the opening and closing of the control valve group (22).

5. The self-adjusting system for the suspended underwater docking platform according to claim 4 is characterized in that: The dry compartment (15) is provided with a hydraulic control device (19) and an AC drive motor (20); The posture control module (4) sends a control signal to the hydraulic control device (19), controls the AC drive motor (20) through the hydraulic control device (19), and controls the opening and closing of the control valve group (22) through the AC drive motor (20).

6. The self-adjusting system for the suspended underwater docking platform according to claim 4 is characterized in that: The wet tank (16) is connected to the compensation oil bag (17) via an oil suction filter (24); The control valve group (22) is connected to the wet tank (16) via a high-pressure filter (21); The dry compartment (15) is provided with an electrical interface (25) and an oil circuit interface (26).

7. The self-adjusting system for the suspended underwater docking platform according to claim 4 is characterized in that: The docking platform comprises: a main control cabin (6), a docking device (27), a push-out / retracting mechanism (14), a buoy (28), an anchor (29), an anchor cable (30), a main frame (5) and a platform frame (10); The platform frame (10) is arranged on the main frame (5), the buoyancy adjustment module (1) is arranged on the main frame (5), and the power control module (2) is arranged on the main frame (5); The main control cabin (6), the docking device (27) and the buoy (28) are arranged on the main frame (5), and the push-out / retracting mechanism (14) is connected to the docking device (27); The anchor (29) is connected to the main frame (5) via the anchor cable (30).

8. A method for autonomously adjusting the posture of a suspended underwater docking platform, characterized in that: The self-adjusting system for the suspended underwater docking platform according to claim 7 comprises the following steps: Step S1: receiving the posture data collected by the posture sensor (12) of the collection and perception module (3) in real time through the posture control module (4), and comparing the received posture data with the set posture data. When the posture deviation between the two does not meet the set requirements, the adjustment steps of step S2 and step S3 are performed; Step S2: the posture data includes the pitch angle α and the roll angle β of the docking platform. According to the positive and negative values ​​of the pitch angle α and the roll angle β, the heights of the multiple azimuth angles of the docking platform are sorted. Based on the chasing leveling method, the piston cylinder (8) that maintains the unchanged displacement volume is confirmed and is used as the chasing target; Step S3: Analyze the attitude deviation between each azimuth angle and the pursuit target through the attitude control module (4), analyze the filling and drainage requirements of the piston cylinder (8) at each azimuth angle according to the attitude deviation, and convert it into the displacement of the filling and drainage mechanism (7) at each azimuth angle, transmit the instruction to the power control module (2) through the attitude control module (4), and further decompose the instruction through the power control module (2), control the direction and opening of the electric proportional reversing valve of the control valve connected to each of the filling and drainage mechanisms (7) in the control valve group, drive the piston (9) to move up and down through the telescopic legs (11), adjust the filling and drainage of the piston cylinder (8) at each azimuth angle, change the drainage volume, and adjust the buoyancy of the platform at each azimuth angle; Step S4: Repeat steps S1 to S3 to continuously reduce the posture deviation until the posture deviation between the collected posture data and the set posture data is within the set range, thereby achieving posture adjustment.

9. The method for autonomously adjusting the attitude of a suspended underwater docking platform according to claim 8, characterized in that: In the step 2, in combination with the movement direction of the docking device (27), the piston cylinder (8) that maintains a constant displacement volume is determined as the pursuit target; When the docking device (27) is inside the docking platform, the docking platform is in a balanced state; When the docking device (27) is pushed out of the docking platform by the push-out / retract mechanism (4), the docking platform tends to tilt forward, with the piston cylinder (8) at the highest point as a target to be chased; When the docking device (27) is retracted into the docking platform by the push-out / retract mechanism (4), the docking platform tends to tilt backward, with the piston cylinder (8) at the lowest point as the target.

10. The method for autonomously adjusting the attitude of a suspended underwater docking platform according to claim 8, characterized in that: The buoyancy adjustment modules (1) are arranged at four azimuth angles of the docking platform; The power control module (2) changes the piston adjustment speed by changing the opening size of the electric proportional reversing valve of the filling and drainage mechanism (7) to set the piston h at each azimuth angle. i The rate of change of the hydraulic oil flow Q through the electric proportional reversing valve i Proportional to: Where i = 1, 2, 3, 4; k i is the proportionality coefficient associated with the i-th filling and drainage mechanism (7), reflecting the effect of flow rate on the piston change rate per unit time; Hydraulic oil flow rate Q i The opening u of the electric proportional reversing valve i Decide, assuming there is a linear relationship between the two: Q i =c i u i Among them, c i is the proportional coefficient related to the characteristics of the i-th electric proportional directional valve. In summary, piston h i The relationship between the rate of change and the opening of the electric proportional reversing valve: Piston h i Displacement H i With buoyancy F i The relationship between is linear, expressed as: F i =εH i Where ε is the proportionality coefficient related to the docking platform and buoyancy; Calculate the required buoyancy F according to the pitch angle α and roll angle β of the docking platform's current attitude i , determine the opening u of each electric proportional reversing valve i , an adaptive control algorithm is used to achieve real-time adjustment of the dynamic characteristics of the system. The specific expression is as follows: F f1 +F f2 +F f3 +F f4 =W+T ff1 y1+F f2 y2+F f3 y3+F f4 y4=0 F f1 x1+F f2 x2+F f3 x3+F f4 x4=0 e x ＝α-α target e y ＝β-β target Where W is the underwater net weight of the docking platform, L x , L y are the length and width of the platform, k and λ are adaptive parameters, ΔU is the control law, e is the attitude error, is the rate of change of error, F f1 、F f2 、F f3 、F f4 is the buoyancy change provided by the buoyancy adjustment module (1) at each azimuth angle, T is the vertical component of the tension of the anchor cable (30) on the docking platform, y1, y2, y3, y4, x1, x2, x3, x4 respectively represent the distances between each of the charging and discharging mechanisms and the geometric center point of the docking platform on the X-axis and the Y-axis, α target , β target They respectively represent the target values ​​of the pitch angle α and the roll angle β, and ex and ey respectively represent the difference between the real-time value and the target value of the pitch angle α and the roll angle β.

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