Path following control method, device, equipment and medium for magnetically levitated underwater robot

Abstract

The present invention provides a path following control method, device, equipment and medium for a magnetically levitated underwater robot, which relates to the field of path following control of underwater robots. The method breaks through the bottleneck of motion control of traditional underwater robots in complex environments through an intelligent control architecture that integrates electromagnetic drive, magnetic levitation matrix and real-time positioning system. In terms of dynamic modeling, the interaction between magnetic force and fluid resistance is taken into account to accurately characterize the motion characteristics of the robot underwater. A nonlinear control strategy combining Lyapunov stability theory with sliding mode control is adopted to design a trajectory tracking controller with strong robustness to ensure that the robot can operate stably and efficiently along a predetermined trajectory in a complex underwater environment. This invention not only significantly improves the maneuverability and operation accuracy of underwater robots, but also provides a more reliable solution for fields such as ocean exploration, resource development and environmental monitoring, showing huge application potential and market value.

Description

Technical Field

[0001] The present invention relates to the technical field of underwater robot path following control, and in particular to a magnetic levitation underwater robot path following control method, device, equipment and medium. Background Art

[0002] In today's era of booming marine resource development and underwater scientific research, underwater robots, as pioneers in underwater exploration, are becoming increasingly important. From deep-sea mineral exploration to marine ecosystem monitoring, from underwater infrastructure inspection and maintenance to underwater archaeological excavation and research, underwater robots are ubiquitous. However, as their application scenarios continue to expand and become more complex, underwater robots face unprecedented challenges in motion control, particularly in the critical function of path following control.

[0003] Traditional underwater robots mostly rely on mechanical propulsion systems, such as propellers and water jets. While these propulsion methods are technically mature, their performance in the complex and ever-changing underwater environment has gradually exposed numerous issues. For example, in turbulent water, robots struggle to maintain a stable posture and precise trajectory, and are easily displaced by the current, resulting in significant path deviations. Faced with complex seabed terrain and obstacles, traditional propulsion systems, due to their mechanical structure, lack flexibility and are unable to react quickly to avoid obstacles, increasing the risk of collision and reducing mission efficiency.

[0004] Furthermore, traditional propulsion systems generate significant mechanical noise during operation, which can interfere with the underwater robot's sensor system, affecting its perception of the surrounding environment. It can also negatively impact the living environment of underwater organisms, hindering the protection of marine ecosystems. Furthermore, the mechanical structure of traditional propulsion methods is complex, requiring regular maintenance and upkeep, increasing the cost and difficulty of maintaining the robot.

[0005] With the continuous advancement of science and technology, magnetic levitation technology has gradually entered people's horizons and demonstrated tremendous application potential in a variety of fields. The core of magnetic levitation technology is to use the interaction of magnetic fields to achieve the suspension and motion control of objects. It offers significant advantages such as non-contact, low friction, and high precision. When magnetic levitation technology is introduced to the field of underwater robotics, it provides new solutions to the problems existing in traditional propulsion systems.

[0006] However, applying magnetic levitation technology to path-following control for underwater robots is not without its challenges. Firstly, the underwater environment is complex and ever-changing, and the propagation and distribution of magnetic fields in water are affected by numerous factors, such as water conductivity, underwater topography, and surrounding metal objects. This makes it difficult for magnetically levitation underwater robots to precisely control the magnetic field during actual operation, thus affecting their path-following accuracy. Secondly, magnetically levitation underwater robots require precise motion control in three-dimensional space. However, existing magnetic levitation control technologies are mostly designed for two-dimensional surfaces or simple environments, making them inadequate for the requirements of three-dimensional motion control in complex underwater environments. Furthermore, energy consumption is a concern during the operation of magnetically levitation underwater robots. Because the magnetic levitation system requires a continuous magnetic field to maintain the robot's suspension and motion, its energy consumption is relatively high. Optimizing the energy efficiency of the magnetic levitation system and reducing the robot's energy consumption while ensuring path-following control accuracy and stability is also a pressing issue.

[0007] In general, although magnetic levitation technology provides a new solution for underwater robot path-following control, it still faces many technical difficulties and challenges in practical applications. Therefore, there is an urgent need for an innovative magnetic levitation underwater robot path-following control method that can effectively overcome the shortcomings of existing technologies, improve the path-following accuracy, stability, and flexibility of underwater robots in complex underwater environments, and reduce energy consumption to meet the growing demand for underwater operations.

[0008] In view of this, this application is filed. Summary of the Invention

[0009] The present invention provides a path following control method, device, equipment and medium for a magnetically suspended underwater robot, which can at least partially improve the above-mentioned problems.

[0010] To achieve the above object, the present invention adopts the following technical solutions:

[0011] A path following control method for a magnetically suspended underwater robot, comprising:

[0012] Obtain the position of the magnetic levitation underwater robot base in space collected by the locator, and establish a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and physical principles;

[0013] Based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space and the kinematic model of the magnetic levitation underwater robot base, the steady-state error of the position of the magnetic levitation underwater robot base is calculated, and the position of the magnetic levitation underwater robot base is adjusted according to the steady-state error so that the magnetic levitation underwater robot base can move stably along the desired path.

[0014] The present invention also provides a path following control device for a magnetically suspended underwater robot, comprising:

[0015] A kinematic model building unit is used to obtain the position of the magnetic levitation underwater robot base in space collected by the locator, and to build a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and the principles of physics;

[0016] The steady-state error calculation unit is used to calculate the steady-state error of the position of the magnetic levitation underwater robot base based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space and the kinematic model of the magnetic levitation underwater robot base, and adjust the position of the magnetic levitation underwater robot base according to the steady-state error so that the magnetic levitation underwater robot base can move stably along the desired path.

[0017] The present invention also provides a magnetic levitation underwater robot path following control device, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the magnetic levitation underwater robot path following control method as described in any one of the above items.

[0018] The present invention also provides a readable storage medium storing a computer program, wherein the computer program can be executed by a processor of a device where the storage medium is located to implement the path following control method of a magnetically levitated underwater robot as described in any one of the above.

[0019] In summary, the core of the path-following control method for a magnetically levitated underwater robot lies in significantly improving the robot's motion control performance in complex environments through advanced control strategies and system architecture. Specifically, based on an integrated motion control system comprising an electromagnetic drive, a magnetically levitated underwater robot base, and a positioner, this system combines electromagnetic drive technology, high-precision positioning feedback, and dynamic modeling methods to accurately simulate and control the underwater motion behavior of the magnetically levitated robot. Furthermore, by incorporating Lyapunov stability theory and sliding mode control technology, an efficient nonlinear control scheme is designed that ensures the robot's stable and precise movement along a predetermined path in the presence of multiple interference factors. This innovative method not only effectively addresses the many challenges faced by traditional underwater robots in path control but also provides a more reliable solution for the application of underwater robots in fields such as marine resource exploration and environmental monitoring, demonstrating significant technical advantages and broad application potential. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 11 is a flow chart of a path following control method for a magnetically suspended underwater robot provided by the first embodiment of the present invention;

[0021] Figure 2 This is a framework diagram of a motion control system provided by an embodiment of the present invention;

[0022] Figure 3 It is a module schematic diagram of a path following control device for a magnetically levitated underwater robot provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be described in further detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] refer to Figure 1 、 Figure 2 As shown, the first embodiment of the present invention discloses a path-following control method for a magnetically levitated underwater robot. The method can be executed by a path-following control device for a magnetically levitated underwater robot (hereinafter referred to as a control device), and in particular, by one or more processors within the control device, to implement the following method:

[0025] S1, obtaining the position of the magnetic levitation underwater robot base in space collected by the locator, and establishing a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and physical principles;

[0026] Specifically, step S1 includes: according to Newton's second law, determining the relationship between the magnetic force and mass of the magnetic levitation underwater robot base during movement, the formula is: ,in, is the mass of the magnetic levitation underwater robot matrix, is the position of the magnetic levitation underwater robot base in space, is the disturbance that the magnetic levitation robot experiences in the environment, For magnetic force, is the viscous resistance;

[0027] Based on Newton's second law, the magnetic force is analyzed in three-dimensional space and obtained ,in, is the magnetic moment, is the magnetic flux density of the magnetic field, is the gradient operator, which is used to calculate the gradient of the field in space;

[0028] According to Stoke's law, the viscous resistance of the magnetic levitation underwater robot body when it moves in the solution medium is determined ,in, is the viscosity coefficient of the liquid, is the radius of the particle, is the movement speed of the magnetic levitation underwater robot base;

[0029] The relationship between the magnetic field force and the horizontal distance between the magnetic levitation underwater robot and the magnetic field center is approximated as a linear relationship, and its mathematical expression is: ,in, for Horizontal distance The relationship coefficient after linearization, is the total magnetic force on the magnetically levitated underwater robot in three-dimensional space, is the magnetic force on the robot in the x direction, is the magnetic force on the robot in the y direction, is the magnetic force on the robot in the z direction, is the transpose symbol, is the current flowing in the electromagnetic coil, is the critical value of the horizontal distance between the electromagnetic actuator and the robot. Once this critical value is exceeded, the magnetic field force decreases as the distance increases;

[0030] Set horizontal distance , and based on the above formula, the kinematic model of the magnetic levitation underwater robot base is obtained: ,in, is the position of the central axis of the magnetic field in the plane, is the position of the magnetic levitation underwater robot base on the plane, is the Stokes drag coefficient, For disturbance.

[0031] In this embodiment, the path following control method of the magnetic levitation underwater robot is based on an integrated motion control system combined with electromagnetic drive technology, high-precision positioning feedback and dynamic modeling methods, which can accurately simulate and control the motion behavior of the magnetic levitation robot underwater. The system includes an electromagnetic drive, a magnetic levitation underwater robot base and a locator. First, the position information of the magnetic levitation underwater robot base in space is obtained through the locator. As a key sensing component, the locator can provide real-time and accurate feedback on the spatial position of the robot base, providing basic data support for subsequent control strategies. Based on these position data and physical principles, a kinematic model of the magnetic levitation underwater robot base is established, which is a key step in achieving precise path control.

[0032] Specifically, based on Newton's second law, the relationship between the force and mass experienced by the magnetic levitation underwater robot's base during motion is thoroughly analyzed, clarifying the forces acting on the robot's base as it moves in space. Furthermore, a detailed analysis of magnetic force is conducted in three dimensions. Magnetic force is the core driving force for the motion of the magnetic levitation underwater robot's base. Using the magnetic force formula, the magnitude and direction of the magnetic force acting on the robot's base under different magnetic field conditions can be accurately calculated, providing a key basis for controlling its motion trajectory. This precise modeling of magnetic force enables this method to effectively regulate the robot's base's motion in complex magnetic field environments, significantly improving the accuracy and stability of path control.

[0033] Furthermore, considering that the motion of a magnetically levitated underwater robot's base in a solution medium is inevitably affected by viscous drag, an expression for viscous drag is determined based on Stokes' law. This formula accurately quantifies the effect of viscous drag on the robot's base motion, allowing for effective compensation through control strategies, reducing path deviations caused by viscous drag and further optimizing the robot's motion performance.

[0034] To simplify the model and improve control effectiveness, the researchers approximated a linear relationship between the magnetic field force and the horizontal distance between the maglev underwater robot and the magnetic field center. This linearization not only simplified the mathematical model and reduced computational complexity, but also made the controller design more intuitive and efficient. By introducing this approximate relationship, the system's response speed and stability were significantly improved while maintaining control accuracy, making the horizontal motion of the maglev underwater robot's base smoother and more controllable.

[0035] After clarifying the expressions for magnetic force and viscous drag, the authors set the horizontal distance and, combining the above formulas, ultimately derived the kinematic model of the magnetically levitated underwater robot's base. The second-order and first-order derivatives of the robot's position represent its acceleration and velocity, respectively. This kinematic model comprehensively describes the robot's base's horizontal motion, taking into account the combined effects of magnetic force and viscous drag. Based on this model, a more precise and effective control strategy can be designed to achieve precise control of the magnetically levitated underwater robot's base motion, enabling it to operate stably and efficiently along a pre-set path.

[0036] Through the above implementation steps, a precise kinematic model was successfully established, providing a solid theoretical foundation for path-following control of the magnetically levitated underwater robot. This model not only improves the accuracy and stability of path control but also enhances the robot's adaptability and flexibility in complex underwater environments, enabling it to maintain stable motion despite various interference factors, significantly improving the underwater robot's operational efficiency and reliability.

[0037] S2, based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space and the kinematic model of the magnetic levitation underwater robot base, calculates the steady-state error of the position of the magnetic levitation underwater robot base, and adjusts the position of the magnetic levitation underwater robot base according to the steady-state error so that the magnetic levitation underwater robot base can move stably along the desired path.

[0038] Specifically, step S2 includes: according to the SMC principle, setting the synovial surface to ,in, is a constant, represents the tracking error, The desired position of the magnetic levitation underwater robot base on the synovial surface At , the tracking error converges to zero;

[0039] The kinematic model of the magnetic levitation underwater robot base is rewritten into an exponential form: ,in, , , is the actual position of the magnetic levitation underwater robot base, For the controller;

[0040] Substitute the synovial surface formula into the exponential form kinematic model and take the derivative to obtain the synovial surface derivative: ,set up ,get ,in, is the thickness of the synovial surface, is a saturation function.

[0041] When judged hour, , select the Lyapunov function , and substitute the derivative of the synovial surface into the Lyapunov function and perform the derivation to obtain: ,in, is the reaching law of synovial control; , Heng is established, ,at this time The minimum value of , the synovial surface can reach the synovial surface in a limited time, is the frequency in the sinusoidal disturbance, For time.

[0042] In this example, a sliding surface was carefully designed based on the principles of sliding mode control (SMC). The core of this design is to ensure that the tracking error on the sliding surface converges to zero, accurately guiding the robot base along the desired path, thereby achieving high-precision path following. Next, the kinematic model of the magnetically levitated underwater robot base was rewritten in exponential form, simplifying the model's complexity and facilitating subsequent control design. This simplified expression allows for more intuitive analysis and design of control strategies to achieve precise control of the robot base's motion.

[0043] To further optimize the control strategy, the sliding surface formula was substituted into the exponential kinematic model and differentiated to obtain the sliding surface derivative. To ensure the stability and rapid convergence of the sliding surface, a saturation function was introduced and the sliding surface thickness was set. By replacing the traditional sign function with a saturation function, system chattering was effectively avoided, thereby improving the robustness and stability of the control system.

[0044] During the control process, it is necessary to monitor the status of the synovial surface in real time. When , the Lyapunov function is selected, and the derivative of the synovial surface is substituted into the Lyapunov function for derivation; by analyzing the derivative of the Lyapunov function, it can be seen that hour, In this case, the synovial surface can reach the synovial surface within a limited time, and The minimum value of This process not only ensures the rapid convergence of the tracking error, but also significantly improves the response speed and stability of the system.

[0045] Preferably, after determining that the synovial surface has been reached, , , Laplace transform is performed on the synovial surface to obtain ,in, is the output of the first-order filter;

[0046] According to the steady-state error and Further derivative of the synovial surface is obtained ,in, Synovial surface The value at steady state;

[0047] Will Converge to the preset value ,at this time, , Laplace transform is performed on the derived sliding membrane surface to obtain , ,in, For disturbance The Laplace transform of For disturbance The value at steady state;

[0048] Will Substitute the steady-state error In the equation, the steady-state error is: .

[0049] In this embodiment, after the sliding surface of the magnetically levitated underwater robot's base reaches the preset sliding surface, the sliding surface is first subjected to a Laplace transform. This process converts complex dynamic processes in the time domain into an algebraic expression in the frequency domain, simplifying the analysis process and improving computational efficiency. The Laplace transform yields a frequency-domain expression for the sliding surface, which can be further simplified into the output form of a first-order filter. This first-order filter not only effectively smooths the control signal but also improves the system's response speed and stability.

[0050] Next, the sliding surface is further differentiated based on the steady-state error. This process yields a derivative expression for the sliding surface. This expression clearly demonstrates the relationship between the rate of change of the sliding surface and the steady-state error, providing an important basis for subsequent control adjustments. This dynamic adjustment ensures that the sliding surface quickly stabilizes after reaching the sliding surface and that the tracking error converges to the preset value.

[0051] Furthermore, to further optimize control, the sliding membrane surface, after converging to a preset value, is subjected to a Laplace transform, enabling a more precise analysis of the system's steady-state behavior. Further frequency-domain analysis of the Laplace transform yields the steady-state error, enabling precise calculation of the system's steady-state error and adjustment of control parameters to achieve more accurate path following.

[0052] The implementation of step S2 not only improves the path-following accuracy of the magnetically levitated underwater robot in complex underwater environments, but also significantly enhances the stability and reliability of the system. By introducing the Laplace transform and first-order filter, noise and interference in the dynamic process can be more effectively processed, thereby achieving smoother motion control.

[0053] In summary, this paper focuses on the field of magnetically levitated underwater robots (AUVs) and proposes an innovative path-following control method designed to significantly improve the robot's motion control performance in complex underwater environments. This method analyzes an intelligent control system that integrates electromagnetic drive, high-precision positioning feedback, and dynamic modeling to achieve precise path-following control of the AUV's base. The core of this method lies in further integrating Lyapunov stability theory with the principles of sliding mode control (SMC) to design a nonlinear control strategy that effectively resists external interference, ensuring that the robot base maintains stable and efficient motion along a predetermined trajectory in complex underwater environments.

[0054] Specifically, the robot's base's position in space is first acquired in real time through a positioner, and its kinematic model is established based on the principles of physics. This model comprehensively considers key factors such as magnetic force and viscous resistance, providing a solid theoretical foundation for subsequent control strategies. By introducing the sliding mode control principle, a sliding membrane surface is designed, which allows the tracking error to converge to zero on the sliding membrane surface, thereby achieving high-precision path following. Furthermore, the sliding membrane surface is processed using mathematical tools such as the Laplace transform, optimizing the smoothness and response speed of the control signal, significantly improving the stability and reliability of the system.

[0055] Compared with existing technologies, this method has the following advantages: 1. Through precise dynamic modeling and advanced control strategies, it significantly improves the path-following accuracy of the magnetically levitated underwater robot base, enabling it to stably track the desired motion trajectory in complex underwater environments. 2. The introduced sliding mode control principle and Laplace transform processing not only enhance the system's anti-interference ability, but also improve the control system's response speed and stability. 3. This method also effectively reduces path deviations caused by external factors such as water flow and obstacles, improving the robot's adaptability and flexibility in dynamic environments.

[0056] Overall, the proposed path-following control method for magnetically levitated underwater robots is not only innovative in theory but also demonstrates significant advantages in practical applications. Through optimized control strategies and system architecture, it provides a more reliable solution for the application of magnetically levitated underwater robots in fields such as marine resource exploration and environmental monitoring, with broad application prospects and market value.

[0057] See also Figure 3 A second embodiment of the present invention provides a path following control device for a magnetically suspended underwater robot, comprising:

[0058] The kinematic model building unit 101 is used to obtain the position of the magnetic levitation underwater robot base in space collected by the locator, and to build a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and the principles of physics;

[0059] The steady-state error calculation unit 102 is used to calculate the steady-state error of the position of the magnetic levitation underwater robot base based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space and the kinematic model of the magnetic levitation underwater robot base, and adjust the position of the magnetic levitation underwater robot base according to the steady-state error so that the magnetic levitation underwater robot base can move stably along the desired path.

[0060] The third embodiment of the present invention provides a magnetic levitation underwater robot path following control device, which includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements the magnetic levitation underwater robot path following control method as described in any one of the above items.

[0061] A fourth embodiment of the present invention provides a readable storage medium storing a computer program, wherein the computer program can be executed by a processor of a device where the storage medium is located to implement the path following control method of a magnetically levitated underwater robot as described in any one of the above.

[0062] Illustratively, the above-mentioned various devices and various process steps can be implemented by a computer program. The computer program can be divided into one or more units. The one or more units are stored in the memory and executed by the processor to complete the present invention.

[0063] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.

[0064] The memory can be used to store the computer programs and / or modules. The processor implements the various functions of the present invention by running or executing the computer programs and / or modules stored in the memory and accessing the data stored in the memory. The memory may primarily include a program storage area and a data storage area. The program storage area may store an operating system and at least one application required for a function (such as a sound playback function, an image playback function, etc.); the data storage area may store data generated based on the use of the mobile phone (such as audio data, a phone book, etc.). Furthermore, the memory may include high-speed random access memory and non-volatile memory, such as a hard disk, internal memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one disk storage device, a flash memory device, or other volatile solid-state storage device.

[0065] If the integrated unit of the electronic device or printer is implemented as a software functional unit and sold or used as a standalone product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention can implement all or part of the process steps in the above-mentioned method embodiments by using a computer program to instruct the relevant hardware. The computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of each of the above-mentioned method embodiments. The computer program includes computer program code, which can be in source code form, object code form, executable file, or some intermediate form. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal, and software distribution medium. It should be noted that the content of the computer-readable medium can be appropriately increased or decreased based on the requirements of legislation and patent practice in a jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media does not include electric carrier signals and telecommunication signals.

[0066] It should be noted that the device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed across multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present embodiment. In addition, in the drawings of the device embodiments provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines. A person of ordinary skill in the art can understand and implement the present invention without inventive effort.

[0067] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A path following control method for a magnetically levitated underwater robot, characterized in that: include: Obtain the position of the magnetic levitation underwater robot base in space collected by the locator, and establish a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and physical principles; Based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space, and the kinematic model of the magnetic levitation underwater robot base, the steady-state error of the magnetic levitation underwater robot base position is calculated, and the position of the magnetic levitation underwater robot base is adjusted according to the steady-state error so that the magnetic levitation underwater robot base can move stably along the desired path; The kinematic model of the magnetic levitation underwater robot base is established according to the position of the magnetic levitation underwater robot base in space and the principles of physics. Specifically: According to Newton's second law, the relationship between the magnetic force and mass of the magnetic levitation underwater robot base during movement is determined as follows: ,in, is the mass of the magnetic levitation underwater robot matrix, is the position of the magnetic levitation underwater robot base in space, is the disturbance that the magnetic levitation robot experiences in the environment, For magnetic force, is the viscous resistance; Based on Newton's second law, the magnetic force is analyzed in three-dimensional space and obtained ,in, is the magnetic moment, is the magnetic flux density of the magnetic field, is the gradient operator, which is used to calculate the gradient of the field in space; According to Stoke's law, the viscous resistance of the magnetic levitation underwater robot body when it moves in the solution medium is determined ,in, is the viscosity coefficient of the liquid, is the radius of the particle, is the movement speed of the magnetic levitation underwater robot base; The relationship between the magnetic field force and the horizontal distance between the magnetic levitation underwater robot and the magnetic field center is approximated as a linear relationship, and its mathematical expression is: ,in, for Horizontal distance The relationship coefficient after linearization, is the total magnetic force on the magnetically levitated underwater robot in three-dimensional space, For robots Direction of magnetic force, For robots Direction of magnetic force, For robots Direction of magnetic force, is the transpose symbol, is the current flowing in the electromagnetic coil, is the critical value of the horizontal distance between the electromagnetic actuator and the robot. Once this critical value is exceeded, the magnetic field force decreases as the distance increases; Set horizontal distance , and based on the above formula, the kinematic model of the magnetic levitation underwater robot base is obtained: ,in, is the position of the central axis of the magnetic field in the plane, is the position of the magnetic levitation underwater robot base on the plane, is the Stokes drag coefficient, For disturbance.

2. The path following control method of a magnetically suspended underwater robot according to claim 1, characterized in that: Based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space and the kinematic model of the magnetic levitation underwater robot base, the steady-state error of the position of the magnetic levitation underwater robot base is calculated, specifically: According to the SMC principle, the synovial surface is set to ,in, is a constant, represents the tracking error, The desired position of the magnetic levitation underwater robot base on the synovial surface At , the tracking error converges to zero; The kinematic model of the magnetic levitation underwater robot base is rewritten into an exponential form: ,in, , , is the actual position of the magnetic levitation underwater robot base, For the controller; Substitute the synovial surface formula into the exponential form kinematic model and take the derivative to obtain the synovial surface derivative: ,set up ,get ,in, is the thickness of the synovial surface, is a saturation function.

3. The path following control method of a magnetically suspended underwater robot according to claim 2, characterized in that: Also includes: When judged hour, , select the Lyapunov function , and substitute the derivative of the synovial surface into the Lyapunov function and perform the derivation to obtain: ,in, Control the approach law for the synovium; in, , Heng is established, ,at this time The minimum value of , the synovial surface can reach the synovial surface in a limited time, is the frequency in the sinusoidal disturbance, For time.

4. The path following control method of a magnetically suspended underwater robot according to claim 3, characterized in that: Also includes: After reaching the synovial surface, , , Laplace transform is performed on the synovial surface to obtain ,in, is the output of the first-order filter; According to the steady-state error and Further derivative of the synovial surface is obtained ,in, Synovial surface The value at steady state; Will Converge to the preset value ,at this time, , Laplace transform is performed on the derived sliding membrane surface to obtain , ,in, For disturbance The Laplace transform of For disturbance The value at steady state; Will Substitute the steady-state error In the equation, the steady-state error is: .

5. A path following control device for a magnetically suspended underwater robot, characterized in that: include: A kinematic model building unit is used to obtain the position of the magnetic levitation underwater robot base in space collected by the locator, and to build a kinematic model of the magnetic levitation underwater robot base based on the position of the magnetic levitation underwater robot base in space and the principles of physics; a steady-state error calculation unit, configured to calculate a steady-state error of the position of the magnetic levitation underwater robot base based on Lyapunov stability theory, the position of the magnetic levitation underwater robot base in space, and a kinematic model of the magnetic levitation underwater robot base, and adjust the position of the magnetic levitation underwater robot base according to the steady-state error so that the magnetic levitation underwater robot base can perform stable motion along a desired path; The kinematic model of the magnetic levitation underwater robot base is established according to the position of the magnetic levitation underwater robot base in space and the principles of physics. Specifically: According to Newton's second law, the relationship between the magnetic force and mass of the magnetic levitation underwater robot base during movement is determined as follows: ,in, is the mass of the magnetic levitation underwater robot matrix, is the position of the magnetic levitation underwater robot base in space, is the disturbance that the magnetic levitation robot experiences in the environment, For magnetic force, is the viscous resistance; Based on Newton's second law, the magnetic force is analyzed in three-dimensional space and obtained ,in, is the magnetic moment, is the magnetic flux density of the magnetic field, is the gradient operator, which is used to calculate the gradient of the field in space; According to Stoke's law, the viscous resistance of the magnetic levitation underwater robot body when it moves in the solution medium is determined ,in, is the viscosity coefficient of the liquid, is the radius of the particle, is the movement speed of the magnetic levitation underwater robot base; The relationship between the magnetic field force and the horizontal distance between the magnetic levitation underwater robot and the magnetic field center is approximated as a linear relationship, and its mathematical expression is: ,in, for Horizontal distance The relationship coefficient after linearization, is the total magnetic force on the magnetically levitated underwater robot in three-dimensional space, For robots Direction of magnetic force, For robots Direction of magnetic force, For robots Direction of magnetic force, is the transpose symbol, is the current flowing in the electromagnetic coil, is the critical value of the horizontal distance between the electromagnetic actuator and the robot. Once this critical value is exceeded, the magnetic field force decreases as the distance increases; Set horizontal distance , and based on the above formula, the kinematic model of the magnetic levitation underwater robot base is obtained: ,in, is the position of the central axis of the magnetic field in the plane, is the position of the magnetic levitation underwater robot base on the plane, is the Stokes drag coefficient, For disturbance.

6. A path following control device for a magnetically suspended underwater robot, characterized in that: The method comprises a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor, wherein when the processor executes the computer program, the path following control method of the magnetic levitation underwater robot according to any one of claims 1 to 4 is implemented.

7. A readable storage medium, characterized in that: A computer program is stored, and the computer program can be executed by a processor of the device where the storage medium is located to implement the path following control method of the magnetic levitation underwater robot as described in any one of claims 1 to 4.

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