Automatic balancing and posture adjusting type underwater robot

Abstract

The invention discloses an automatic balancing and attitude adjusting type underwater robot, relates to the field of underwater robot control, and aims to solve the problem that an underwater robot is difficult to give consideration to the functions of automatic buoyancy adjustment, attitude control and rapid floating at present. The device comprises a main machine body, a power unit, a control unit, a detection unit, a buoyancy regulation and control unit and a standby power supply, according to the technical scheme, the buoyancy regulation and control unit is regulated in real time through PID control on the basis of attitude data and depth gauge information, buoyancy autonomous balancing of the underwater robot under different loads is ensured, and the tedious balancing weight adjusting process in traditional manual balancing is avoided. During high-speed movement, the automatic balancing and attitude adjusting system can finely adjust the pitch angle and the roll angle of the underwater robot, stably maintain high-speed operation and cooperate with the propeller system to achieve better dynamic response. In addition, the system further has the function of quickly floating through the standby power supply and the buoyancy regulation and control unit under the out-of-control or power-off condition, and the safety of the robot is guaranteed.

Description

Technical Field

[0001] The invention relates to the field of underwater robot control, in particular to an automatic balancing and posture-adjusting underwater robot. Background Art

[0002] With the rapid development of marine engineering technology, underwater robots have been widely used in the inspection and maintenance of infrastructure such as offshore platforms, pipelines, docks, dams, etc. However, due to the complex underwater environment, affected by ocean currents, depth changes and the dynamic changes of the underwater robot itself, the robot will encounter problems with buoyancy and buoyancy center changes during operation, which not only affects its stability but also reduces its operating efficiency.

[0003] At present, in the use of underwater robots, especially in large underwater robots, closed underwater robots and robots equipped with new equipment, balancing operations often involve cumbersome processes. Specifically, when adjusting the buoyancy and posture of the robot, it is usually necessary to adjust its buoyancy and posture by adding and removing counterweights or repeatedly hanging them. This operation is not only time-consuming and laborious, but also unable to adapt to the buoyancy changes of the robot in real time when it is working. Therefore, there is an urgent need for an underwater robot system that can automatically adjust the buoyancy and posture to achieve efficient operation.

[0004] In addition to the need for balance and attitude adjustment, underwater robots also need to have emergency response capabilities during operations. In particular, when encountering dangerous situations, the robot needs to be able to quickly float to a safe area to ensure the safety of operators and equipment. However, existing technologies are difficult to take into account the functions of automatic buoyancy adjustment and attitude control as well as rapid floating, and still rely on manual intervention or complex control strategies.

[0005] Therefore, designing an underwater robot system that can automatically adjust buoyancy and posture and quickly float up in dangerous situations is an important requirement to improve the operating efficiency, stability and safety of underwater robots. Summary of the invention

[0006] The technical problem to be solved and the technical task proposed by the present invention are to improve and perfect the existing technical solutions, and provide an automatic balancing and attitude adjustment underwater robot, so as to improve the operation stability and efficiency of the underwater robot and provide emergency buoyancy capability. To this end, the present invention adopts the following technical solutions.

[0007] An automatic balancing and attitude-adjusting underwater robot, comprising: The main body includes a frame module, a buoyancy shell and a tail wing. An electronic cabin is installed inside the frame module. The buoyancy shell is installed on the outer ring of the frame module to adjust the buoyancy and protect precision components. A power unit, including a propeller, is mounted on the frame module to drive the main body to move underwater; The detection unit includes an optical detection unit, an acoustic detection unit, a posture sensor, and a magnetic detector, which is used to feedback the position and posture information of the robot itself and the detection information required for the operation; A buoyancy control unit, including a compressed air cabin, which adjusts the buoyancy and attitude of the main body by adjusting the volume of the compressed air cabin. The buoyancy control unit is installed on the robot frame module. A buoyancy control unit is installed in front, rear, left and right of the frame module to adjust the buoyancy of the bow, stern and port and starboard of the robot separately, and comprehensively adjust the attitude of the whole machine. The control unit includes an electronic cabin connected to the thruster and the attitude sensor; the control unit adjusts the buoyancy of each group of buoyancy control units in real time according to the information fed back by the attitude sensor, so as to realize the autonomous buoyancy trimming of the underwater robot under different loads, and optimizes the attitude of the underwater robot during high-speed movement through the automatic trimming and attitude adjustment system when the underwater robot moves at high speed; Backup power supply: installed inside the electronic cabin. When the robot floats up to avoid danger in an emergency, the backup power supply starts and drives the buoyancy control unit to realize the emergency floating of the robot.

[0008] The present invention adopts a design combining a buoyancy control unit with an automatic control system, which can automatically adjust the buoyancy of each group of buoyancy control units in real time according to the feedback information of the robot's attitude sensor, ensuring that the underwater robot always maintains the best buoyancy and attitude state. This design overcomes the complexity and inefficiency of the traditional manual adjustment of the counterweight and buoyancy, realizes the automatic adjustment of the robot's buoyancy and attitude, and improves work efficiency.

[0009] By installing buoyancy control units on the front, back, left and right of the robot, each buoyancy control unit can adjust the buoyancy of the corresponding part separately, thereby achieving precise control of the robot's posture. Compared with the traditional single buoyancy adjustment method, it can more accurately adjust the buoyancy and posture in different directions, enhancing the robot's operational stability, especially in the ever-changing underwater environment.

[0010] The buoyancy control system of the present invention can automatically perform balancing according to the buoyancy requirements under different loads, ensuring that the robot is always in the best buoyancy state. In addition, when the robot moves at high speed, the system can adjust the posture in real time, optimize the movement state, reduce the impact of posture changes on the robot's movement, and improve the stability and efficiency of the robot in high-speed movement.

[0011] By combining multiple detection units (optical, acoustic detection units, attitude sensors, magnetic detectors, etc.), the present invention can obtain the position and attitude information of the underwater robot in real time, and adjust the buoyancy and attitude according to this information to achieve precise control. This enables the robot to respond quickly to environmental changes in complex underwater environments and optimize its operating performance.

[0012] The automatic balancing and attitude adjustment system not only improves the stability of the robot's operation, but also helps the robot deal with dangerous situations that may be encountered during underwater operations. Through precise buoyancy adjustment and attitude control, the robot can quickly adjust its attitude or float up in an emergency to ensure safe operation.

[0013] The automated buoyancy adjustment system reduces the need for manual intervention, and the robot can automatically complete the adjustment based on real-time feedback data. This makes the robot easier and more reliable to operate, and can maintain stable performance during long-term operations, reducing the burden on operators and improving the efficiency and safety of operations.

[0014] The backup power supply can be quickly started when the robot is in an emergency state (such as loss of control, system failure or unexpected power failure), providing the necessary power support to ensure that the robot can perform floating and risk avoidance operations in an emergency and avoid potential safety risks. When the underwater robot encounters an abnormal situation, the backup power supply can quickly drive the buoyancy control unit to automatically float the robot to a safe surface. This can effectively prevent the robot from being in dangerous water depths for a long time or being unable to recover due to a failure, reducing the risk of damage or loss of the robot. The design of the backup power supply provides a redundant solution for the robot. When the main power supply fails, the backup power supply can continue to provide energy support to ensure that the robot can still operate normally in an emergency and improve the reliability and stability of the system. The backup power supply combined with the automatic control of the buoyancy control unit enables the robot to automatically trigger floating in an emergency, avoiding manual intervention and improving the robot's adaptive ability in complex underwater environments. The configuration of the backup power supply allows operators to be more assured when the robot performs complex tasks. If the robot fails or loses control, the safety guarantee provided by the backup power supply can effectively prevent the robot from sinking into deep water or being unable to recover, thereby improving the safety of the operation process. The backup power supply, as a backup for the power system, enhances the robot's fault tolerance in harsh underwater environments. Even if a power failure occurs, the robot can rely on the backup power supply to ensure the most basic buoyancy adjustment function, thereby achieving emergency surfacing.

[0015] As a preferred technical means: the buoyancy control unit also includes a sliding cabin cover, an adjusting motor, a screw, a screw nut, and a connecting shaft; the sliding cabin cover is matched with the inner wall of the compressed air cabin for sliding, and the connecting shaft is "U"-shaped, one end is connected to the sliding cabin cover, and the other end is connected to the screw nut; the adjusting motor drives the screw to rotate, and the screw nut moves accordingly, and drives the sliding cabin cover connected to the connecting shaft to slide in the compressed air cabin, thereby realizing the adjustment of the cavity inside the compressed air cabin.

[0016] By adjusting the motor to drive the screw to rotate, the screw nut drives the connecting shaft and the sliding hatch to move, so as to achieve precise adjustment of the volume of the internal cavity of the compressed air cabin. It can achieve fine adjustment of the volume of the compressed air cabin, and then accurately control the buoyancy change of the underwater robot, ensuring that the robot can maintain the best buoyancy state in various working environments.

[0017] The combination of the sliding hatch and the regulating motor reduces the complex valves and air pressure control systems that may exist in traditional buoyancy regulating devices, and simplifies the mechanical structure. The regulating motor drives the screw to rotate, and the control method is simpler and more efficient, which can quickly respond to buoyancy regulation needs and improve the stability of the system and the accuracy of operation.

[0018] The U-shaped connecting shaft and the reliable connection with the sliding hatch cover and the screw nut make the entire buoyancy control process more stable and reliable. The close fit between the sliding hatch cover and the inner wall of the compressed air cabin effectively reduces the risk of air leakage or misadjustment, and improves the long-term stability and durability of the system.

[0019] The sliding hatch design can achieve a wide range of buoyancy adjustment within a limited space without taking up too much structural space, which is especially important for space-constrained equipment such as underwater robots. In addition, the adjustment mechanism and spatial layout within the system make buoyancy adjustment more flexible and adaptable to different environments and needs.

[0020] The motor drives the screw to rotate, and the adjustment speed is relatively fast, so that the robot can respond to changes in the underwater environment in a timely manner, such as changes in water flow, changes in equipment load, etc.

[0021] This technical solution can be combined with a control unit to automatically adjust the movement of the sliding hatch, achieving real-time optimization and adjustment of the robot's buoyancy and posture. Combined with the robot's sensor feedback, it can automatically adjust the buoyancy in different working environments and states, thereby reducing manual intervention and improving work efficiency and safety.

[0022] Due to the efficient coordination between the regulating motor and the mechanical structure, the system can achieve precise buoyancy adjustment with low energy consumption, which is especially important for underwater robots, which are usually energy-constrained devices.

[0023] As an optimal technical means: a regulating cabin shell is provided on the periphery of the compressed air cabin, the screw rod and screw rod nut are located in the cavity surrounded by the compressed air cabin and the regulating cabin shell, and one end of the connecting shaft passes through the regulating cabin shell and is connected to the screw rod nut.

[0024] By placing the screw and screw nut in the cavity surrounded by the compressed air cabin and the regulating cabin shell, both can be effectively protected from external water pressure, corrosive substances or mechanical damage. The regulating cabin shell serves as a protective shell, which enhances the sealing of the mechanical structure and prevents moisture or impurities from entering the buoyancy control system, thereby improving the long-term reliability and stability of the system.

[0025] Placing the lead screw and lead screw nut in the cavity between the compressed air chamber and the regulating chamber shell effectively saves space inside the underwater robot. The spatial layout inside the robot is optimized to the maximum extent, ensuring that more functional modules can be compactly integrated without affecting other functions or operating performance of the robot.

[0026] Since the screw and screw nut are located in a closed cavity, the erosion and wear of these moving parts by the external environment (such as seawater, sand, etc.) can be avoided, which improves the durability of the entire buoyancy control system. Even in a complex marine environment, the mechanical parts can maintain high efficiency for a long time.

[0027] The connecting shaft passes through the housing of the regulating chamber and is connected to the screw nut to form a more accurate and stable transmission system. This can reduce the looseness and error between mechanical parts and improve the accuracy of buoyancy adjustment. This ensures that when adjusting the volume of the buoyancy chamber, the system moves more smoothly and responds more accurately.

[0028] The outer shell of the regulating cabin surrounds the compressed air cabin and provides additional support for it, which can enhance the pressure resistance of the entire buoyancy regulating unit in high water pressure environments. Whether in deep-sea operations or in environments with different water depths, the stability of the compressed air cabin is effectively guaranteed to avoid deformation or damage to the cabin due to excessive water pressure.

[0029] The combination of the connecting shaft and the screw nut makes the adjustment process of the compressed air chamber more uniform and smooth, improving the accuracy and consistency of buoyancy control. This is crucial for the robot to maintain stability and operating efficiency in complex underwater environments, and can ensure that the robot can automatically adjust buoyancy and posture based on real-time feedback.

[0030] As the preferred technical means: each buoyancy adjustment unit is provided with a plurality of connecting shafts and screw rods matching the number of connecting shafts, each of the screw rods is provided with the screw nut, the connecting shaft is connected to the screw nut through an annular movable frame, and the movable frame and the screw nut are connected by screws; the tail of the compressed air cabin is provided with an outward-turned folded edge, and the outer shell of the adjustment cabin is a hollow barrel; the barrel bottom of the outer shell of the adjustment cabin matches the folded edge of the compressed air cabin; a first through hole is opened in the middle position of the barrel bottom of the outer shell of the adjustment cabin, and a plurality of second through holes are arranged on the outer periphery of the first through hole; the second through holes are evenly arranged in the circumferential direction; the inner shaft sections of all connecting shafts are passed through the first through hole; the outer shaft sections corresponding to the connecting shafts are passed through the second through hole; a dynamic sealing end cover with a sealing member is provided between the outer shaft section and the outer shell of the adjustment cabin.

[0031] Each buoyancy adjustment unit is equipped with multiple connecting shafts and matching screws. This multi-axis structure makes the buoyancy adjustment process more refined and balanced. Through the joint action of multiple screws, more precise buoyancy adjustment can be achieved, avoiding the uneven adjustment caused by a single bearing and screw, and improving the stability and response accuracy of the entire system.

[0032] The design of connecting the connecting shaft through the annular moving frame and the lead screw nut can reduce the friction between the parts and make the movement smoother. The design of the annular moving frame not only strengthens the stability of the connecting shaft, but also effectively disperses the forces from different directions to avoid structural damage caused by a single force point.

[0033] By matching the seal between the outer shaft section and the outer shell of the regulating cabin, seawater penetration and corrosion can be effectively avoided, ensuring the sealing and waterproofness of the system in the underwater environment. It can effectively prevent moisture from entering the system, reduce the impact of external factors such as water pressure and corrosion on the system, and extend the service life of the underwater robot.

[0034] The tail of the compressed air cabin is equipped with an outward-turned folded edge, which cooperates with the barrel bottom of the regulating cabin shell to increase the pressure resistance of the entire structure. Especially in deep-sea environments, underwater robots are subjected to high water pressure. The folded edge design and sealing structure provide better protection and effectively avoid deformation or damage in high-pressure water environments.

[0035] The outer shell of the regulating cabin adopts a hollow barrel design, and the overall structure is compact, which is easy to install and maintain. At the same time, the design of the first through hole and the second through hole ensures that the connecting shaft can be smoothly installed through the corresponding channel, avoiding a complicated installation process and reducing the difficulty of operation. The simplicity of the design also facilitates later inspection and maintenance, especially reducing the difficulty of manual operation during underwater operations.

[0036] The bottom of the regulating cabin shell is provided with multiple second through holes, and the through holes are evenly arranged, so that the pressure from all directions can be evenly distributed, thus enhancing the stability of the regulating cabin. The design of each connecting shaft and screw nut helps to improve the pressure resistance of the buoyancy regulating cabin, ensuring long-term stable operation in harsh underwater environments.

[0037] Multi-axis connection and multiple screw nuts ensure that the system can cope with different buoyancy adjustment requirements. The robot can adjust each buoyancy unit according to different working environments or task requirements, accurately control the buoyancy and balance state of the robot, and improve the adaptability of the system.

[0038] The load of the regulating cabin is more evenly distributed during operation, avoiding excessive wear of mechanical parts. The efficient coordination of the screw rod and the connecting shaft reduces unnecessary mechanical losses, thereby improving the long-term stability and energy-saving effect of the system.

[0039] As a preferred technical means: the barrel mouth of the regulating cabin shell is provided with an end cover; the regulating motor is provided in the cavity between the end cover and the regulating cabin; the end of the regulating cabin close to the end cover extends outward to form a positioning ring, and the outer periphery of the positioning ring matches the inner wall of the regulating cabin shell; an assembly hole is provided on the positioning ring; and the regulating motor drives the screw to rotate through a gear pair.

[0040] This technical solution sets up an adjustment motor in the cavity of the adjustment cabin and designs a positioning ring so that the adjustment motor can be stably installed in the cabin, and the outer periphery of the positioning ring matches the inner wall of the adjustment cabin shell, effectively ensuring the fixed position and stability of the motor. This simplifies the installation process of the motor, reduces the error and adjustment difficulty during installation, and also facilitates later maintenance and replacement.

[0041] The adjustment motor drives the screw to rotate through the gear pair to achieve more efficient force transmission and precise control. The design of the gear pair makes the transmission process smoother and more efficient, and can accurately drive the screw to adjust the buoyancy adjustment device, ensuring that the robot's buoyancy adjustment system can work efficiently and stably in an underwater environment.

[0042] The design of the positioning ring not only effectively ensures the stability of the regulating motor, but also reduces the displacement or loosening of mechanical parts caused by vibration or external force. Through precise matching, the positioning ring strengthens the combination between the regulating cabin shell and the end cover, making the entire system more stable when working underwater and avoiding structural damage under high water pressure.

[0043] The end cover can seal the cavity where the regulating motor is located, ensuring that the motor and its connecting components are not directly exposed to the underwater environment, and effectively preventing moisture, impurities and other corrosive substances from entering the motor cavity, thereby improving the service life of the motor and the stability of the system.

[0044] Compared with direct drive, the gear pair can better distribute the force transmission, reduce the direct friction between the motor and the screw, reduce wear, extend the service life of the system, and reduce maintenance costs.

[0045] Since the transmission between the motor and the screw rod adopts a gear pair, precise control can be achieved and system failures caused by excessive friction can be avoided. This makes the robot more stable when working underwater for a long time, reduces the occurrence of system failures, and improves the reliability of underwater operations.

[0046] The positioning ring design ensures the smooth operation of the adjustment motor and the screw rod, making the entire adjustment process more uniform and achieving more accurate buoyancy adjustment. The positioning ring ensures the accuracy of the parts matching, so that the buoyancy adjustment unit maintains a high consistency during operation, further improving the stability and accuracy of the robot operation.

[0047] The design of the end cap and the positioning ring ensures the compactness of the overall system, avoids unnecessary space occupation and structural complexity, and optimizes the weight distribution of the robot system. It helps to reduce the weight of the robot, improve its buoyancy adjustment ability, and ensure the flexibility of the robot.

[0048] As an optimal technical means: the power unit is provided with six thrusters, namely two vertical thrusters and four horizontal thrusters; the two vertical thrusters are installed on the front and rear sides of the frame module to control the left and right steering of the robot, and are installed vertically staggered with the horizontal thrusters; four are installed at the stern of the robot to provide the thrust source for the robot to move forward.

[0049] The configuration of two vertical thrusters and four horizontal thrusters greatly improves the underwater robot's control ability in three-dimensional space. The vertical thrusters can accurately control the robot's up and down movement, while the horizontal thrusters can provide thrust for the robot to move forward, backward, and rotate. The two vertical thrusters can effectively adjust the robot's left and right steering by arranging them on the front and back sides. The staggered installation of vertical and horizontal thrusters improves the robot's response speed and steering flexibility.

[0050] The staggered installation of horizontal and vertical thrusters helps the robot maintain a more stable posture when performing complex operations. Especially when working underwater, the robot needs to deal with ocean currents, obstacles or mission changes. By precisely adjusting the thrust of the thrusters, the robot can better maintain balance and quickly adjust in different directions.

[0051] The configuration of six thrusters can evenly distribute the thrust, avoiding overloading of a single thruster, thus improving the overall efficiency of the system. The vertical thrusters and horizontal thrusters have clear division of labor, which can provide more stable propulsion in underwater environments and avoid dragging or tilting caused by unbalanced thrusters or uneven loads.

[0052] With two vertical thrusters installed on the front and rear sides, the robot can make more precise vertical adjustments, making navigation more accurate. Especially in complex underwater environments, the robot can effectively respond to instantaneous tilt or other posture changes, thereby improving the accuracy of operations.

[0053] The design of the six-thruster configuration enables the underwater robot to adapt to more complex mission requirements. For example, when performing tasks that require delicate operations such as pipeline inspection and equipment testing, the robot can accurately control the motion trajectory and steering angle, improving operational efficiency and mission success rate.

[0054] Configuring multiple thrusters can disperse the burden of each thruster and avoid the problem of reduced efficiency or failure of a single thruster due to long-term overload. The coordinated work of multiple thrusters optimizes energy efficiency and improves the reliability of the system in long-term use.

[0055] Since the robot is equipped with multiple thrusters, if one thruster fails, the other thrusters can continue to provide the necessary propulsion to ensure that the underwater robot can continue its mission or return safely. This redundant design greatly reduces the risk caused by thruster failure during operation.

[0056] Underwater robots need to operate in different environments, such as complex scenes such as ocean currents and obstacles. The layout of the six thrusters makes the robot more adaptable, able to better cope with environmental changes and ensure the smooth completion of the mission.

[0057] As a preferred technical means: the optical detection unit includes: an LED underwater light and a camera; the optical detection unit is embedded in the bow of the robot, and two LED underwater lights are installed on both sides of the camera, both of which are fixed to the frame module by screws, and the communication power supply is connected to the electronic cabin through a connector; The acoustic detection unit includes: a sonar, which is installed on the top of the front side of the underwater robot; The attitude sensor includes: a depth meter, an altimeter, an inertial measurement unit and a Puller velocimeter; The magnetic detector is installed on the frame module, on the left and right sides of the frame module, below the attitude control, and is used to detect damage to the submarine pipeline; The detection unit is used to feed back the position and posture information of the robot itself and the detection information required for the operation.

[0058] The combination of the optical detection unit, acoustic detection unit, attitude sensor and magnetic detector of this technical solution can comprehensively collect information in underwater environment. The optical detection unit (LED underwater light and camera) can clearly capture underwater images and is suitable for performing inspection tasks within the visible light range; the acoustic detection unit (sonar) provides efficient detection capabilities in turbid waters or low visibility environments; the attitude sensor (depth gauge, altimeter, inertial measurement unit and Puller velocimeter) ensures accurate positioning and real-time monitoring of the robot's depth, motion state and speed; the magnetic detector is specifically used to detect damage to metal objects such as submarine pipelines, increasing the safety and accuracy of operations.

[0059] The combined use of depth gauges, altimeters, inertial measurement units and pulser velocimeters can accurately measure the position, depth, attitude and speed of underwater robots. This not only improves the navigation accuracy of the robot in a dynamic environment, but also corrects the attitude in real time to ensure the stability of the operation.

[0060] Different sensors can provide feedback from many aspects. The optical detection unit provides the operator with clear image feedback for easy visual inspection; the acoustic detection unit uses sonar to scan the underwater environment and identify obstacles, submarine pipelines and other targets; the magnetic detector is specifically used to detect damage to submarine pipelines or other metal structures, greatly improving the accuracy of damage detection.

[0061] The underwater working environment is complex, with factors such as lighting conditions, visibility, and ocean currents varying greatly. The optical detection unit is equipped with an LED underwater light to ensure clear visual detection under different lighting conditions; the sonar of the acoustic detection unit is not affected by light and can continue to work effectively in environments with poor water quality or low visibility. The coordination of multiple sensors enables the robot to adapt to different working environments, enhancing its reliability and flexibility in operation.

[0062] Since the detection unit can provide real-time feedback on the robot's posture and position, the robot can adjust its posture, speed and position in time during the operation to avoid errors or deviations affecting task execution, thereby improving operation efficiency and the success rate of task completion. At the same time, the detection of submarine pipeline damage through magnetic detectors can provide accurate information during pipeline inspections and other tasks, so that maintenance or repair work can detect potential problems earlier and avoid further damage.

[0063] The use of multi-sensor integration enables underwater robots to obtain comprehensive real-time feedback when performing complex tasks, especially in tasks that require precise operation and environmental perception, such as underwater pipeline inspection and environmental monitoring. The robot can use comprehensive detection information to determine and avoid obstacles, correct posture, and adjust movement trajectory to ensure the smooth progress of the mission.

[0064] The power supply and communication of all detection units are connected to the electronic compartment through connectors, which simplifies the wiring of the electrical system and makes the system easier to manage and maintain. The design of the connector improves the modularity and replaceability of the system and ensures efficient performance in long-term operation.

[0065] As a preferred technical means: the buoyancy control unit is controlled by a fuzzy PID controller, and the three parameters in the PID controller are corrected and adjusted in real time according to the system error and error change rate.

[0066] The fuzzy PID controller of this technical solution combines the advantages of fuzzy control and traditional PID control, and can effectively handle the nonlinearity, time-varying and uncertainty existing in the system. By correcting and adjusting the three parameters in the PID controller in real time, the system can adaptively adjust the working state of the buoyancy control unit, thereby more accurately controlling the adjustment of buoyancy and posture. Especially in a dynamically changing underwater environment, the stability and accuracy of the underwater robot are improved to ensure that it maintains a stable operating state.

[0067] Traditional PID controllers require fixed control parameters to be set in advance, while fuzzy PID controllers can dynamically adjust the parameters in the PID controller based on the actual error and error change rate of the system. This enables the system to respond in real time and perform optimized control under different working states and environmental conditions. This is especially important for underwater robots operating in complex environments, as factors such as water flow, depth changes, and loads may change at any time.

[0068] In underwater environments, robots are often affected by complex external factors such as flow, pressure, and temperature. Traditional PID controllers may not perform well in such complex nonlinear and multivariable environments. Fuzzy PID controllers can process these complex factors through fuzzy logic, do not rely on precise mathematical models, flexibly respond to changes in underwater environments, avoid over- or under-regulation during the control process, and improve control effects.

[0069] The fuzzy PID controller can adjust the PID parameters through fuzzy rules and real-time feedback, reducing the complexity of manual adjustment and automatically optimizing parameters. The automated adjustment process can effectively reduce the difficulty of system debugging, especially during underwater operations, and can quickly adapt to various environmental changes and improve work efficiency.

[0070] Since the fuzzy PID controller can dynamically adjust according to the system errors and changes, the underwater robot can better adapt to external interference and changes. For example, environmental factors such as ocean currents, water temperature, and pressure changes may affect buoyancy and posture. The fuzzy PID controller can automatically correct the control strategy based on real-time feedback to ensure the robustness of the system. Even in the case of large interference and errors, the robot can still maintain good performance.

[0071] During the buoyancy adjustment process, the robot may face complex situations such as load changes and posture adjustments. The fuzzy PID controller can optimize the working state of the buoyancy adjustment unit in real time, ensuring that the robot's buoyancy and posture are always in the best state, avoiding the decrease in operating efficiency due to uneven buoyancy or unstable posture, especially during high-speed movement or rapid posture adjustment, and can maintain a stable control effect.

[0072] This technical solution uses a fuzzy PID controller to enable the underwater robot to intelligently adjust its buoyancy without human intervention. The system can automatically adjust the control strategy according to the current state, adapt to various complex working environments and task requirements, and improve the robot's adaptive ability.

[0073] Due to the real-time adjustment characteristics of the fuzzy PID controller, the underwater robot can control buoyancy and posture more accurately, thereby reducing ineffective or excessive energy consumption, improving energy efficiency, and extending the robot's working time.

[0074] As a preferred technical means: the tail wing is in a horizontal "[" shape, and the stability index of the tail wing is Derived through CFD simulation;

[0075] in, is a dimensionless static stability index, and its value is ,in It refers to the angle of attack The pitching moment generated is It refers to the angle of attack The vertical force generated on the vertical fuselage, L is the length of the fuselage; is a dimensionless dynamic stability index, and its value is , Refers to the pitch angular velocity of the fuselage The resulting rotational torque, Refers to the pitch angular velocity of the fuselage The rotational force generated when When the ROV is unstable, it is difficult to maintain a balanced state; when When , ROV stability is moderate; When the ROV is stable, it is more likely to recover to a balanced state when it is disturbed. The tall airfoil serves as the tail.

[0076] Calculating the stability indicators of the tail by using CFD simulation , can more accurately evaluate and optimize the design of the tail. The value means that the tail can recover to a balanced state more quickly and stably when subjected to external disturbances (such as ocean currents, vibrations, etc.), thereby improving the overall stability of the underwater robot. This is crucial for underwater operations in long-term and complex environments, and avoids the robot's posture loss of control or reduced operating efficiency due to the instability of the tail.

[0077] Dimensionless static stability index obtained through CFD simulation calculation and dimensionless dynamic stability index , which can provide accurate performance evaluation basis for tail wing design; the numerical simulation analysis method is more scientific and accurate than the traditional empirical design method, which helps to ensure that the design results meet the needs of practical applications.

[0078] According to the stability index The calculation results can select the airfoil with the best stability. The high-stability tail can make the underwater robot better adapt to changes in the external environment (such as flow rate changes, improper control, etc.), and more effectively maintain the robot's balance underwater, reducing attitude fluctuations or control problems caused by improper tail design.

[0079] when When the value is between 0.7 and 0.8, the ROV (remotely operated underwater robot) shows better stability and is more likely to return to a balanced state when subjected to instantaneous interference. This means that by optimizing the tail design, the underwater robot can resist sudden interference (such as water flow fluctuations, obstacle collisions, etc.) when working underwater, ensuring the continuity and efficiency of the operation.

[0080] A tail with good stability can reduce the frequency of posture adjustment of underwater robots, thereby reducing energy consumption and improving task execution efficiency. In addition, in more complex or dangerous underwater environments, good tail stability helps maintain the stability and accuracy of the robot in the operating area, avoiding failure or repeated operations due to posture imbalance.

[0081] Using CFD simulation to optimize the tail design helps improve the reliability of the design. Through accurate fluid dynamics calculations, the performance of the tail under different working conditions can be predicted, reducing the possibility of unexpected problems in actual work, thereby improving the overall reliability of the underwater robot system.

[0082] Optimizing the stability of the tail wing through CFD simulation during the design phase can effectively reduce the complexity of later debugging. Since the stability of the tail wing has been fully predicted and verified, the adjustments and changes that may occur during the actual test process will be greatly reduced, thereby saving development costs and time.

[0083] By calculating the stability index By choosing a high-stability tail wing, the underwater robot can maintain good adaptability in different working conditions, especially in changing water flow environments. This adaptability enhances the robot's ability to operate in various complex underwater environments, whether it is deep-sea exploration or near-shore operations.

[0084] As a preferred technical means: the control unit adjusts the robot posture based on the buoyancy-thruster hybrid posture method, comprehensively controls the thruster and the buoyancy control unit, and realizes the underwater robot posture adjustment while maintaining the current underwater robot operating speed; The center of gravity of the robot before adjustment is G(x G ,y G ,z G ), the buoyancy center is O , the center of gravity position remains unchanged before and after buoyancy adjustment, and the center of gravity position after adjustment is G(x G ,y G ,z G ), the buoyancy center position after adjustment is , the robot adjusts the inclination angle to ; The adjustment formula is:

[0085]

[0086] .

[0087] This technical solution uses a buoyancy-thruster hybrid attitude control method, combined with a buoyancy adjustment unit and a thruster, to accurately adjust the attitude of the underwater robot in the water, especially when delicate operations are required (such as underwater pipeline inspection, maintenance, etc.). By adjusting the center of buoyancy and center of gravity, the robot's attitude can be effectively optimized to ensure its stability in complex environments.

[0088] When working underwater, maintaining a proper posture is crucial for the stability of the robot. By adjusting the robot's posture through this technical solution, the robot's motion trajectory and posture can be optimized while ensuring the operating speed, avoiding the decrease in motion efficiency or instability caused by improper posture, and improving the efficiency and stability of the operation.

[0089] By using a mixture of thrusters and buoyancy adjustment units for attitude control, excessive reliance on a single thruster can be reduced, thereby avoiding frequent starting or adjustment of the thruster during the adjustment process and reducing energy consumption. This helps to extend the robot's operating time and improve energy efficiency.

[0090] This technical solution enables the underwater robot to adaptively adjust its posture in a complex underwater environment by controlling the buoyancy and thrusters in real time. For example, the robot can adjust its posture in real time according to changes in the external environment such as water flow changes and depth changes, maintain stability, and avoid posture imbalance caused by external disturbances.

[0091] The robot's adjustment angle under different conditions is calculated by the formula ( , , ), which can accurately analyze and adjust the robot's posture, allowing the robot to efficiently adjust to the best angle during various operations. This is especially important for high-precision tasks (such as when working on the seabed).

[0092] This technical solution can perform real-time posture adjustment according to the needs of different operating environments, adapt to various underwater working environments such as deep sea or nearshore, complex terrain or stable areas, and improve the robot's adaptability and operating ability.

[0093] The robot can flexibly adjust its posture according to different operation stages or task requirements. For example, when high-precision positioning or operation is required, the robot can adjust to the best posture; when moving at high speed or adjusting the operation position, the robot can maintain the appropriate posture to optimize the propulsion effect and ensure the smooth progress of the task.

[0094] Through the automated attitude adjustment system, underwater robots can reduce human intervention or reliance on external equipment, and improve the autonomy and intelligence of operations. This allows underwater robots to work independently for a long time, and is particularly suitable for unmanned complex or dangerous underwater environments.

[0095] Beneficial effects: 1. The automatic balancing and posture adjustment underwater robot equipped with a buoyancy control unit described in the present invention can realize automatic leveling of the underwater robot before launching, simplify the robot balancing process, and improve work efficiency.

[0096] 2. The buoyancy-thruster hybrid posture method is used to adjust the robot's underwater motion posture, which has a larger adjustment range and more stable adjustment than the traditional method.

[0097] 3. It can make the robot float up quickly when it is out of control or power off, thus reducing property losses.

[0098] 4. This technical solution performs dynamic closed-loop control based on attitude data and depth gauge information, and adjusts the buoyancy of each group of buoyancy adjustment mechanisms in real time through PID, which can realize the autonomous buoyancy balance of underwater robots under different loads, and solves the cumbersome process of repeated disassembly and assembly of counterweights in the traditional manual balance process of large underwater robots. In addition, the autonomous balance of this system can achieve relatively consistent underwater buoyancy requirements, which is conducive to the refined motion control of underwater robots. When the underwater robot moves at high speed, the automatic balance and attitude adjustment system can optimize the posture during high-speed movement, fine-tune the pitch angle or roll angle of the underwater robot, so that it can maintain high-speed movement smoothly, and combine control with the thruster system to achieve better dynamic response. BRIEF DESCRIPTION OF THE DRAWINGS

[0099] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0100] Figure 2 It is a schematic diagram of the structure of the present invention from a side view after a portion of the buoyancy shell is removed.

[0101] Figure 3 It is a schematic diagram of the structure of the electronic cabin of the present invention.

[0102] Figure 4 It is a schematic diagram of the three-dimensional structure of the posture control unit of the present invention.

[0103] Figure 5 It is a schematic diagram of the cross-sectional structure of the posture control unit of the present invention.

[0104] Figure 6 It is the buoyancy regulation block diagram of the fuzzy PID controller of the present invention.

[0105] Figure 7 It is the automatic leveling flow chart of the present invention.

[0106] Figure 8 It is an emergency floating flow chart of the present invention.

[0107] Fig. 9 It is a flow chart of the buoyancy-thruster hybrid attitude adjustment of the present invention.

[0108] Fig.10 It is the calculation flow domain and grid division diagram of the high-speed ROV system of the present invention.

[0109] Fig.11 It is the NACA0032 airfoil diagram.

[0110] Fig.12 It is the NACA0012 airfoil diagram.

[0111] Fig.13 This is the NACA airfoil diagram with an inclination angle of 15°.

[0112] Fig.14 It is the NACA_V airfoil diagram.

[0113] In the figure: 1, main body; 11, frame module; 12, buoyancy shell; 13, lifting ring; 14, tail wing; 2. Power unit; 21. Propeller; 3. Control unit; 31. Electronic compartment; 4. Detection unit; 41. Optical detection unit; 411. LED underwater light; 412. Camera; 42. Acoustic detection unit; 421. Sonar; 43. Attitude sensor; 431. Depth gauge; 432. Altimeter; 433. Inertial measurement unit; 434. Doppler velocimeter; 44. Magnetometer; 5. Buoyancy control unit; 501. Compressed air cabin; 502. Sliding cabin cover; 503. Adjustment motor; 504. Screw; 505. Screw nut; 506. Connecting shaft; 507. Moving frame; 508. End cover; 509. Adjustment chamber housing; 510. Transmission gear; 511. Dynamic seal end cover; 512. Connector; 6. Backup power supply. DETAILED DESCRIPTION

[0114] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings.

[0115] like Figure 1-3 As shown, the underwater robot of the present invention includes a main body 1, a power unit 2, a control unit 3, a detection unit 4, a buoyancy control unit 5 and a backup power supply 6, which cooperate to realize the underwater robot's movement, posture adjustment, detection, control and other functions. Specifically: 1. Main body 1: The main body 1 includes a frame module 11, a buoyancy shell 12, a lifting ring 13, and a tail wing 14; the frame module 11 is rectangular as a whole, an electronic cabin 31 is installed inside, and two horizontally arranged thrusters 21 are installed at the front and rear.

[0116] Frame module 11: As the core structure of the main body 1, it provides support for all components in the robot.

[0117] Buoyancy shell 12: installed on the outer ring of the frame module 11, it is the outermost layer of the robot body, mainly used to adjust buoyancy and protect precision components from water pressure and corrosion.

[0118] Lifting ring 13: installed on the robot frame module 11, located at the horizontal center of gravity, used for mounting and lifting the underwater robot.

[0119] Tail 14: Located on the frame module 11 at the tail of the robot, on the outside of the robot's horizontal main thrust, it is used to reduce the thrust loss of the robot's main thrust during operation, improve the robot's movement stability, reduce fluid resistance and eddy currents, and ensure that the robot operates stably in different postures.

[0120] 2. Power unit 2: The power unit 2 includes a propeller 21 mounted on the frame module 11 to drive the main body 1 to move underwater.

[0121] Horizontal thrusters 21: There are 6 thrusters 21 in total, 2 of which are installed on the front and rear sides of the frame module 11, mainly used to control the left and right steering of the robot; 4 are installed at the stern of the robot to provide the main thrust source for the robot to move forward.

[0122] Vertical thrusters 21: Two vertical thrusters 21 are installed on the front and rear sides of the frame module 11, and are installed vertically and staggered with the horizontal thrusters 21 to adjust the pitch angle of the robot.

[0123] 3. Control unit 3: The control unit 3 includes an electronic compartment 31 , which is installed at the internal center of gravity of the frame module 11 and is responsible for providing power support and communication interface for the propeller 21 , sensors and other electrical components of the whole machine.

[0124] A processor is installed in the electronic cabin 31 for processing information such as the robot's posture and movement and regulating various working parameters of the robot.

[0125] 4. Detection unit 4: The detection unit 4 includes an optical detection unit 41, an acoustic detection unit 42, a posture sensor 43, a magnetic detector 44, etc. The detection unit 4 is used to obtain information such as the underwater environment and the position and posture of the robot itself.

[0126] Optical detection unit 41: includes an LED underwater light 411 and a camera 412, which are embedded and installed in the bow of the robot. The LED underwater light 411 and the camera 412 are installed on both sides of the frame module 11, fixed with screws and connected to the electronic cabin 31 through a connector 512 to provide underwater visual images and lighting.

[0127] Acoustic detection unit 42: includes sonar 421, installed on the front top of the underwater robot, responsible for detecting underwater objects through sound waves.

[0128] The posture sensor 43 includes a depth meter 431, an altimeter 432, an inertial measurement unit 433 (IMU) and a Doppler velocimeter 434 (DVL), and is used to monitor the posture, depth, speed and other information of the robot in real time.

[0129] Magnetic detector 44: installed on the left and right sides of the frame module 11 and below the attitude control, used to detect damage to the submarine pipeline or magnetic objects.

[0130] V. Backup power supply 6: The backup power supply 6 is installed inside the electronic compartment 31, such as Figure 3 When the robot encounters an emergency (such as loss of control or power outage), it provides backup power support.

[0131] When the robot is in an emergency state, the backup power supply 6 is started to drive the buoyancy control unit 5 to realize the emergency buoyancy of the robot, ensuring that the robot returns to the water surface safely.

[0132] 6. Buoyancy control unit 5: The buoyancy control unit 5 is used to accurately control the buoyancy and posture of the robot by adjusting the volume of the compressed air cabin 501. The buoyancy control unit 5 includes: a compressed air cabin 501, a sliding cabin cover 502, an adjustment motor 503, a screw 504, a screw nut 505, a connecting shaft 506, a moving frame 507, an end cover 508, an adjustment chamber housing 509, a transmission gear 510, a dynamic seal end cover 511, and a connector 512; the buoyancy and posture of the main body 1 are adjusted by adjusting the volume of the compressed air cabin 501. The buoyancy control unit 5 is installed on the robot frame module 11 through a clamp, and a buoyancy control unit 5 is installed in front, rear, left, and right of the frame module 11, respectively, which can adjust the buoyancy of the bow, stern, and port and starboard of the robot separately, and comprehensively control the posture of the whole machine.

[0133] The buoyancy control unit 5, the compressed air cabin 501 is installed on the regulating cabin shell by screws, the screw rods 504 are evenly installed in the screw rod 504 installation holes on the outer circle of the compressed air cabin 501, and a transmission gear 510 is installed at one end of the screw rod 504; the end cover 508 is installed on the regulating cabin by screws, the regulating motor 503 is installed in the center of the end cover 508, and a transmission gear 510 is installed at the end of the regulating motor 503, which is meshed with the gear at the end of the screw rod 504; the screw rod 504 rotates to drive the screw nut 505 to move, and the moving frame 507 is connected to the screw nut 505 by screws; the connecting shaft 506 connects the sliding cabin cover 502 and the moving frame 507, drives the cabin cover to move back and forth, and adjusts the posture to control the overall volume of the power supply.

[0134] The buoyancy control unit 5 is waterproof and sealed as a whole. A static sealing ring is installed between the outer shell of the adjustment cabin and the end cover 508 and the compressed air cabin 501, and a dynamic sealing ring is installed at the contact between the connecting shaft 506 and the outer shell of the adjustment cabin, so as to realize the waterproof sealing of the overall loading and attitude adjustment system, offset the gravity of the structural parts of the loading and attitude adjustment system, achieve zero buoyancy itself, and all the variable volumes in the cabin realize buoyancy adjustment for the robot.

[0135] The buoyancy control unit 5 is driven by a motor, which drives the gear transmission to drive the screw rod 504 to rotate, and moves the push rod up and down to connect the movable piston cabin cover and the movable frame 507, so that the piston cabin cover moves up and down with the movable frame 507, and the volume of the compressed air cabin 501 changes, thereby realizing the buoyancy adjustment of the robot.

[0136] The buoyancy control unit 5 is controlled by a fuzzy PID controller, such as Figure 6 As shown, the three parameters in the PID controller are corrected and adjusted in real time according to the system error and error change rate, so that the control system can achieve higher dynamic performance and control accuracy, and improve the stability and accuracy of the underwater robot's posture adjustment.

[0137] The present invention can select different posture adjustment methods according to different situations: Attitude adjustment situation 1: In this embodiment, the buoyancy-thruster 21 hybrid attitude method is used to adjust the robot attitude, and the thruster 21 and the buoyancy control unit 5 are comprehensively controlled to make up for the control problem caused by the thrust attenuation of the thruster 21 at high speed. Under the condition of maintaining the current operating speed of the underwater robot, the underwater robot attitude adjustment is achieved. Compared with the traditional attitude control system, the adjustment range is wider, the adjustment is more stable and sensitive. Its principle is as follows Fig. 9 As shown, including: S1: The control unit 3 issues a posture adjustment command; S2: The detection unit 4 transmits the robot's own posture information to the underwater robot control unit 3 to determine whether the robot's current posture meets the command requirements. If so, the command is terminated, otherwise S3 is performed; S3: further determine whether the thruster 21 needs to be adjusted in attitude at this time. If not, the buoyancy control unit 5 is used to adjust the robot attitude alone; if necessary, the thruster 21 is used to perform large-scale attitude adjustment, and the attitude loading system is used to perform attitude fine adjustment; S4: The posture sensor 43 feeds back the current position information to the control unit 3 to determine whether the current posture of the robot meets the command requirements. If so, the command is terminated, otherwise, S3 is performed.

[0138] Attitude adjustment situation 2: In this embodiment, the volume control principle is used to adjust the robot's weight and buoyancy center position, and the buoyancy adjustment modules at different positions are comprehensively adjusted to make up for the control problem caused by the thrust attenuation of the thruster 21 at high speed, and to achieve the overall buoyancy attitude adjustment of the underwater robot, which is more stable and sensitive than the traditional attitude control system. Its principle is as follows Figure 7 As shown, including: S1: The control unit 3 issues a posture adjustment command; S2: The posture sensor 43 of the detection unit 4 transmits the posture information of the robot to the underwater robot control unit 3 to determine whether the overall posture of the robot is leveled at this time. If it is level, the command is terminated; if it is not leveled, S3 is performed; S3: The control unit 3 adjusts the driving motors of each group of buoyancy control units 5 in real time through PID to control the buoyancy of different positions of the robot and adjust the robot as a whole to a horizontal state; S4: The sensor feeds back the current position information to the control unit 3 to determine whether the current posture of the robot meets the command requirements. If so, the command is terminated, otherwise it returns to S3.

[0139] Attitude adjustment situation three: When the underwater robot encounters an emergency situation such as loss of control or accidental power failure, the attitude loading system starts the backup power supply 6, and the overall buoyancy of the attitude loading system reaches the maximum value, so that the robot body can float up to avoid danger. The specific process is as follows Figure 8 As shown: S1: Electronic compartment 31 backup battery power supply; S2: Control unit 3 issues an emergency stop command; S3: Each buoyancy control unit 5 adjusts the buoyancy to the maximum, so that the robot floats up quickly; S4: End command.

[0140] In order to improve the stability of the underwater robot, especially at high speeds, the tail 14 design and stability index are adopted Optimization. Among them:

[0141] In the formula is a dimensionless static stability index, and its value is ,in It refers to the angle of attack The pitching moment generated is It refers to the angle of attack The vertical force generated on the vertical fuselage, L is the length of the fuselage; is a dimensionless dynamic stability index, and its value is , Refers to the pitch angular velocity of the fuselage The resulting rotational torque, Refers to the pitch angular velocity of the fuselage The rotational force generated; when When the ROV is unstable, it is difficult to maintain a balanced state; when When , ROV stability is moderate; When the ROV is in a stable state, it is more likely to recover its equilibrium state when it is disturbed.

[0142] Tail 14 design: This embodiment compares various tail wing designs and selects several typical tail wing designs for analysis. Fig.11 , Fig.12 , Fig.13 and Fig.14 As shown, the airfoil diagrams of NACA0032, NACA0012, NACA 15° and NACA_V tail fins are shown respectively. In order to evaluate the influence of these tail fins on the motion stability of underwater robot (ROV), CFD simulation technology is used in this embodiment. Fig.10 The calculation flow domain and grid division diagram of the high-speed ROV system are shown. During the simulation process, the flow domain is divided into the outer flow domain A, the middle flow domain B and the nearby flow domain C, and the velocity inlet D and the pressure outlet E are set to ensure the accuracy and reliability of the simulation results. Through CFD simulation, the influence of different tail fin designs (including no tail fin, NACA0032, NACA0012, NACA inclination 15° and NACA_V type) on the motion stability of the high-speed ROV is analyzed. According to the simulation results, the motion stability index of the ROV equipped with different tail fins is calculated. The following are the effects of various tail configurations on ROV stability:

[0143]

[0144]

[0145]

[0146]

[0147] The results show that the presence and shape of the tail 14 have a significant impact on the motion stability of the high-speed inspection ROV. The ROV without the tail 14 has poor motion stability and a low stability index; after the tail 14 is installed, the overall motion stability of the ROV is significantly improved. Among the various tail 14 shapes, the ROV with the NACA0012 airfoil has the best stability. The CFD simulation results show that the NACA0012 airfoil tail 14 has a significant positive effect on improving the motion stability of the ROV.

[0148] Therefore, in this embodiment, the NACA0012 airfoil is selected as the tail wing 14 design of the ROV.

[0149] The working principle of posture adjustment is: When the robot adjusts its posture, the buoyancy control unit 5 is mainly used to change the position of the center of buoyancy and the center of gravity, thereby adjusting the robot's inclination angle.

[0150] The center of gravity of the robot before adjustment is G(x G ,y G ,z G ), the buoyancy center is O , the center of gravity position remains unchanged before and after buoyancy adjustment, and the center of gravity position after adjustment is G(x G ,y G ,z G ), the buoyancy center position after adjustment is , the robot adjusts the inclination angle to The adjustment formula is:

[0151]

[0152]

[0153] The posture of the underwater robot is precisely adjusted by calculating the change in the center of buoyancy. The adjustment formula helps determine the pitch, roll and yaw angles of the robot in the underwater environment, that is, the tilt angle of the robot in three-dimensional space. Specifically: : Indicates the tilt angle of the robot in the XY plane (horizontal plane). It determines the robot's posture change in the horizontal plane by calculating the relative change of the center of buoyancy in the X and Y directions. For example, the change in the position of the center of buoyancy will affect the robot's tilt left to right or front to back.

[0154] in,( ) is the position of the center of buoyancy after adjustment, ( ) is the position of the center of buoyancy before adjustment. By comparing the difference between the two, the angle in the XY plane can be obtained.

[0155] : Indicates the tilt angle of the robot on the XZ plane (front view plane), which mainly controls the up and down tilt (pitch angle) of the robot. When the center of buoyancy position changes in the Z direction, it will affect the pitch angle of the robot.

[0156] This formula calculates the pitch angle by comparing the changes in the center of buoyancy in the X and Z directions, helping to adjust the pitch stability of the robot.

[0157] : Indicates the tilt angle of the robot in the YZ plane (side view plane), which is usually related to the lateral stability of the robot, that is, the yaw angle.

[0158] The yaw angle is calculated by comparing the changes in the center of buoyancy in the Y and Z directions to ensure the lateral balance and stability of the robot.

[0159] The posture adjustment method of this embodiment helps to ensure that the underwater robot can accurately control its posture and maintain stability when performing tasks, thereby avoiding control problems caused by unstable posture.

[0160] Through these control parameters, the robot's posture in the water can be accurately adjusted to achieve efficient and stable operation.

[0161] The automatic balancing and posture adjustment underwater robot shown above is a specific embodiment of the present invention, which has embodied the substantial characteristics and progress of the present invention. According to actual use needs and under the guidance of the present invention, equivalent modifications in shape, structure, etc. can be made to it, which are all within the protection scope of this scheme.

Claims

1. An automatic balancing and posture adjustment underwater robot, characterized in that: include: A main body (1), the main body (1) comprising a frame module (11), a buoyancy shell (12) and a tail wing (14), an electronic cabin (31) being installed inside the frame module (11), and the buoyancy shell (12) being installed on the outer ring of the frame module (11) for adjusting buoyancy and protecting precision components; A power unit (2), comprising a propeller (21), mounted on the frame module (11) to drive the main body (1) to move underwater; A detection unit (4), comprising an optical detection unit (41), an acoustic detection unit (42), a posture sensor (43) and a magnetic detector (44), for feeding back position and posture information of the robot itself and detection information required for the operation; A buoyancy control unit (5) comprises a compressed air cabin (501), the buoyancy control unit (5) adjusting the volume of the compressed air cabin (501) to achieve buoyancy and attitude adjustment of the main body (1), the buoyancy control unit (5) being mounted on the robot frame module (11), with a buoyancy control unit (5) being mounted in front, rear, left and right of the frame module (11) respectively, so as to individually adjust the buoyancy of the bow, stern and port and starboard sides of the robot, and comprehensively adjust the attitude of the entire machine; The control unit (3) comprises an electronic cabin (31) connected to the propeller (21) and the attitude sensor (43); the control unit (3) adjusts the buoyancy of each group of buoyancy control units (5) in real time according to information fed back by the attitude sensor (43), thereby realizing autonomous buoyancy trimming of the underwater robot under different loads, and optimizing the attitude of the underwater robot during high-speed movement through an automatic trimming and attitude adjustment system when the underwater robot is moving at high speed; A backup power supply (6) is installed inside the electronic cabin (31). When the robot floats up to avoid danger in an emergency, the backup power supply (6) is started to drive the buoyancy control unit (5) to realize the emergency floating of the robot.

2. The automatic balancing and posture adjustment underwater robot according to claim 1, characterized in that: The buoyancy control unit (5) further comprises a sliding hatch cover (502), an adjustment motor (503), a screw (504), a screw nut (505), and a connecting shaft (506); the sliding hatch cover (502) is matched with the inner wall of the compressed air cabin (501) for sliding, and the connecting shaft (506) is in a "U" shape, with one end connected to the sliding hatch cover (502) and the other end connected to the screw nut (505); the adjustment motor (503) drives the screw (504) to rotate, and the screw nut (505) moves accordingly, and drives the sliding hatch cover (502) connected to the connecting shaft (506) to slide in the compressed air cabin (501), thereby realizing the adjustment of the cavity in the compressed air cabin (501).

3. The automatic balancing and posture adjustment underwater robot according to claim 2, characterized in that: A regulating cabin shell is provided on the outer periphery of the compressed air cabin (501); the screw rod (504) and the screw rod nut (505) are located in a cavity enclosed by the compressed air cabin (501) and the regulating cabin shell; one end of the connecting shaft (506) passes through the regulating cabin shell and is connected to the screw rod nut (505).

4. The automatic balancing and posture adjustment underwater robot according to claim 3, characterized in that: Each buoyancy adjustment unit is provided with a plurality of connecting shafts (506) and screw rods (504) matching the number of the connecting shafts (506), each screw rod (504) is provided with a screw rod nut (505), the connecting shaft (506) is connected to the screw rod nut (505) via an annular movable frame (507), and the movable frame (507) and the screw rod nut (505) are connected via screws; the tail of the compressed air cabin (501) is provided with an outward-turned folded edge, the The regulating cabin shell is in a hollow barrel shape; the barrel bottom of the regulating cabin shell matches the folded edge of the compressed air cabin (501); a first through hole is provided in the middle of the barrel bottom of the regulating cabin shell, and a plurality of second through holes are provided on the periphery of the first through hole; the second through holes are evenly arranged in the circumferential direction; the inner shaft sections of all the connecting shafts (506) are passed through the first through hole; the outer shaft sections corresponding to the connecting shafts (506) are passed through the second through hole; and a dynamic sealing end cover (511) with a sealing member is provided between the outer shaft section and the regulating cabin shell.

5. The automatic balancing and posture adjustment underwater robot according to claim 4, characterized in that: The barrel opening of the regulating cabin shell is provided with an end cover (508); the regulating motor (503) is provided in the cavity between the end cover (508) and the regulating cabin; the end of the regulating cabin close to the end cover (508) extends outward to form a positioning ring, and the outer periphery of the positioning ring matches the inner wall of the regulating cabin shell; the positioning ring is provided with an assembly hole; the regulating motor (503) drives the screw rod (504) to rotate through a gear pair.

6. The automatic balancing and posture adjustment underwater robot according to claim 1, characterized in that: The power unit (2) is provided with six thrusters (21), namely two vertical thrusters (21) and four horizontal thrusters (21); the two vertical thrusters (21) are installed on the front and rear sides of the frame module (11) to control the left and right steering of the robot, and are installed vertically and staggered with the horizontal thrusters (21); and the four thrusters are installed at the stern of the robot to provide the thrust source for the robot to move forward.

7. The automatic balancing and posture adjustment underwater robot according to claim 1, characterized in that: The optical detection unit (41) comprises: an LED underwater light (411) and a camera (412); the optical detection unit (41) is embedded in the bow of the robot, and two LED underwater lights (411) are installed on both sides of the camera (412), and are both fixed to the frame module (11) by screws, and the communication power supply is connected to the electronic cabin (31) through the connector (512); The acoustic detection unit (42) comprises: a sonar (421), the sonar (421) being installed on the top of the front side of the underwater robot; The attitude sensor (43) comprises: a depth meter (431), an altimeter (432), an inertial measurement unit (433) and a Doppler velocimeter (434); The magnetic detector (44) is installed on the frame module (11), on the left and right sides of the frame module (11), below the attitude control, and is used to detect damage to the submarine pipeline; The detection unit (4) is used to feed back the position and posture information of the robot itself and the detection information required for the operation.

8. The automatic balancing and posture adjustment underwater robot according to claim 1, characterized in that: The buoyancy control unit (5) is controlled by a fuzzy PID controller, and three parameters in the PID controller are corrected and adjusted in real time according to the system error and error change rate.

9. The automatic balancing and posture adjustment underwater robot according to claim 1, characterized in that: The tail wing (14) is in a horizontal "[" shape, and the stability index of the tail wing (14) is Derived through CFD simulation; in, is a dimensionless static stability index, and its value is ,in It refers to the angle of attack The pitching moment generated is It refers to the angle of attack The vertical force generated on the vertical fuselage, L is the length of the fuselage; is a dimensionless dynamic stability index, and its value is , Refers to the pitch angular velocity of the fuselage The resulting rotational torque, Refers to the pitch angular velocity of the fuselage The rotational force generated when When the ROV is unstable, it is difficult to maintain a balanced state; when When , ROV stability is moderate; When the ROV is stable, it is more likely to recover to a balanced state when it is disturbed. The tall airfoil serves as the tail.

10. The automatic balancing and posture adjustment underwater robot according to claim 9, characterized in that: The control unit (3) adjusts the robot posture based on a buoyancy-thruster (21) hybrid posture method, and comprehensively controls the thruster (21) and the buoyancy control unit (5), thereby achieving posture adjustment of the underwater robot while maintaining the current operating speed of the underwater robot; The center of gravity of the robot before adjustment is G(x G ,y G ,z G ), the buoyancy center is O , the center of gravity position remains unchanged before and after buoyancy adjustment, and the center of gravity position after adjustment is G(x G ,y G ,z G ), the buoyancy center position after adjustment is , the robot adjusts the inclination angle to ; The adjustment formula is: 。

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