A path tracking control method and system for a surface unmanned vehicle based on pulse correction

Abstract

The application discloses a water surface unmanned ship path tracking control method and system based on pulse correction, relates to the unmanned ship control technical field, and comprises the following steps: establishing a kinematic model and a dynamic model; acquiring a desired path trajectory and position information of the water surface unmanned ship, and combining the kinematic model to construct an outer loop error model of the water surface unmanned ship; designing a guidance law comprising a virtual leader point, a guide speed and a desired yaw angular velocity, and specifying a desired forward speed; acquiring a current forward speed and a yaw angular velocity of the water surface unmanned ship, combining the dynamic model, the desired forward speed and the desired yaw angular velocity to construct an inner loop error model of the water surface unmanned ship; and establishing a controller based on pulse correction according to the inner loop error model to realize water surface unmanned ship path tracking. The application adopts the path tracking control strategy based on pulse correction under a complex unknown water surface environment, and effectively reduces the control cost of unmanned ship path tracking.

Description

Technical Field

[0001] This invention relates to the field of unmanned surface vessel (USV) control technology, and in particular to a path tracking control method and system for USVs based on pulse correction. Background Technology

[0002] Unmanned surface vessels (USVs), as intelligent unmanned platforms integrating modern marine technology, artificial intelligence, robotics, and sensing technology, can autonomously or remotely control navigation on the water surface and perform specific tasks. They possess advantages such as low cost, ease of operation, high level of intelligence, and good flexibility, and have been widely applied in various fields including hydrological monitoring, safety rescue, near-shore patrol, marine surveying, and military security. Compared to traditional manned vessels, USVs, with their strong environmental adaptability and superior maneuverability, can enter shallow waters and complex near-shore waters—areas where traditional vessels are difficult to operate in—effectively reducing mission costs while ensuring personnel safety. The effective execution of tasks such as maritime rescue, obstacle avoidance navigation, multi-vehicle formation, and anti-submarine detection all highly rely on stable and reliable path tracking and control technology, which has become the core support for the intelligent application of USVs.

[0003] The core objective of path tracking control technology is to enable unmanned surface vessels (USVs) to accurately follow a preset path in complex marine environments, and its performance directly determines the mission's effectiveness. Current conventional path tracking control methods mainly include proportional-integral-derivative (PI-DE) control, backstepping control, and model predictive control. These methods achieve path tracking through continuous feedback adjustment or model predictive optimization. In recent years, to conserve control resources, event-triggered control has gained considerable attention in this field. Its core logic is to initiate control actions only when the system state meets preset trigger conditions, reducing redundant operations compared to continuous control.

[0004] However, existing technologies still have significant shortcomings in practical applications: conventional control methods generally have inherent defects such as weak resistance to external interference, high control energy consumption, and high computational complexity, making them difficult to adapt to complex and ever-changing marine environments; event-triggered control usually uses a zero-order hold to maintain the control state between adjacent triggering moments, which can easily lead to high-frequency chattering and redundant control effects in the system state, resulting in increased actuator wear and unnecessary energy loss.

[0005] Meanwhile, facing the strong nonlinearity and time-varying dynamic characteristics of unknown water surface environments, event-triggered strategies lack effective adaptive adjustment capabilities, making it difficult to achieve a balance between control resource conservation, tracking accuracy, and system stability. Existing theoretical and technological explorations in saving control resources have mostly focused on event-triggered control, failing to fundamentally solve the problem of matching control effectiveness with control consumption. How to design a path tracking control scheme that balances low energy consumption, low computational burden, high robustness, and high accuracy has become a key technical challenge that urgently needs to be overcome. Summary of the Invention

[0006] To address the aforementioned issues, this invention proposes a path tracking control method and system for unmanned surface vessels based on pulse correction. This invention employs a path tracking control strategy based on pulse correction in complex and unknown water environments, effectively reducing the control cost of unmanned surface vessel path tracking.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a path tracking control method for unmanned surface vessels based on pulse correction, comprising the following steps:

[0009] Based on the underactuated characteristics of unmanned surface vessels, kinematic and dynamic models are established.

[0010] Obtain the desired path trajectory and the position information of the unmanned surface vessel (USV), and construct the outer loop error model of the USV based on the kinematic model. According to the outer loop error model, design a guidance law including the guiding velocity of the virtual leader point and the desired yaw rate, and specify the desired forward speed.

[0011] The forward speed and yaw rate of the current unmanned surface vessel are obtained. The inner loop error model of the unmanned surface vessel is constructed by combining the dynamic model, the desired forward speed and the desired yaw rate. Based on the inner loop error model, a controller based on pulse correction is established to realize the path tracking of the unmanned surface vessel.

[0012] As an alternative implementation, the kinematic model is represented as follows:

[0013] ;

[0014] ;

[0015] ;

[0016] in, , These are the coordinates of the unmanned surface vessel in the inertial coordinate system. The yaw angle of the unmanned surface vessel. , , They are respectively , , The derivative with respect to time, , , These represent the forward speed, sway speed, and yaw rate of the unmanned surface vessel in the body coordinate system.

[0017] As an alternative implementation, the dynamic model is expressed as follows:

[0018] ;

[0019] ;

[0020] ;

[0021] in, , , The total mass includes both rigid body mass and hydrodynamically added mass. , , This is the corresponding hydrodynamic damping coefficient. , These are the control inputs for the forward direction and yaw rate, respectively.

[0022] As an alternative implementation method, the specific approach to constructing the outer loop error model of the unmanned surface vessel is as follows:

[0023] First, a Serret-Frenet coordinate system and a track coordinate system are established based on the obtained desired path trajectory. Then, based on the curvature characteristics of the desired path trajectory, the kinematic model, and the position information of the unmanned surface vessel (USV), the kinematic model of the USV in the inertial coordinate system is transformed to the Serret-Frenet coordinate system. Finally, in the Serret-Frenet coordinate system, the position error between the USV and the virtual leader point is calculated, and the outer loop error model of the USV is established.

[0024] As an alternative implementation method, the inner-loop error model of the unmanned surface vessel is represented as follows:

[0025] ;

[0026] ;

[0027] in, , For nonlinear hydrodynamic unknown functions, , These are forward speed error and yaw angle error, respectively. , These are the desired forward speed and the desired yaw rate, respectively. , The total mass includes both rigid body mass and hydrodynamically added mass. , These are the control inputs for the forward direction and yaw rate, respectively.

[0028] As an alternative implementation method, when establishing a controller based on impulse correction, an adaptive law estimation is first performed on the nonlinear hydrodynamic unknown function. Specifically, the adaptive law estimation is performed by first decomposing the nonlinear hydrodynamic unknown function into basis functions, then introducing an estimator, and finally designing an adaptive law.

[0029] Secondly, the present invention provides a path tracking control system for unmanned surface vessels based on pulse correction, comprising the following modules:

[0030] The kinematics and dynamics model building module is configured to: establish kinematic and dynamic models based on the underactuated characteristics of unmanned surface vessels;

[0031] The guidance module is configured to: acquire the desired path trajectory and the position information of the unmanned surface vessel, and construct the outer loop error model of the unmanned surface vessel in combination with the kinematic model; and design a guidance law including the guidance velocity of the virtual leader point and the desired yaw rate based on the outer loop error model, and specify the desired forward speed.

[0032] The pulse-correction-based control module is configured to: acquire the current forward speed and yaw rate of the unmanned surface vessel, and construct an inner-loop error model of the unmanned surface vessel by combining the dynamic model, the desired forward speed, and the desired yaw rate; and establish a pulse-correction-based controller based on the inner-loop error model to realize path tracking of the unmanned surface vessel.

[0033] Thirdly, the present invention provides an electronic device, including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when executed by the processor, perform the pulse-corrected path tracking control method for unmanned surface vessels described in the first aspect.

[0034] Fourthly, the present invention provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, perform the pulse-corrected path tracking control method for unmanned surface vessels described in the first aspect.

[0035] Fifthly, the present invention provides a computer program product, including a computer program, which, when executed by a processor, implements the pulse-corrected path tracking control method for unmanned surface vessels described in the first aspect.

[0036] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0037] Based on the curvature characteristics of the desired path trajectory and the kinematics and dynamics principles of unmanned surface vessels, this invention establishes inner and outer loop error models and designs a pulse-corrected controller to achieve low-cost path tracking control. Compared to traditional control methods, this invention introduces a pulse control strategy, fully considering the relationship between continuous control and pulse control, avoiding high-frequency chattering and redundant actions in the control input. Combined with an adaptive strategy for complex water surface environments, it effectively reduces control overhead and enhances the adaptability to water surface environments.

[0038] This invention significantly improves the control robustness and tracking accuracy of unmanned surface vessels (USVs) in unknown and complex water environments. The kinematic and dynamic models established based on the underactuated characteristics of USVs accurately reflect the vessel's motion. The outer-loop error model, combined with Serret-Frenet coordinate transformation and guidance law design, provides precise velocity commands for path tracking. The inner-loop error model, coupled with adaptive laws and pulse correction control, effectively overcomes the influence of nonlinear hydrodynamic terms and time-varying dynamics, achieving a theoretical control accuracy of over 97% and maintaining stable and reliable tracking performance even in complex sea conditions.

[0039] This invention significantly reduces control energy consumption and computational burden during path tracking. The pulse correction controller triggers strong adjustments only at preset discrete moments, replacing energy-intensive continuous control with sparse pulse action. At the same time, it simplifies the estimation process of unknown functions in nonlinear hydrodynamics through a function approximation strategy, eliminating the need for large amounts of training data or complex calculations. While ensuring control performance, it significantly saves control resources and computational costs.

[0040] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0041] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0042] Figure 1 This is a schematic diagram of the movement of the unmanned surface vessel in this invention;

[0043] Figure 2 This is a schematic diagram of the control of the unmanned surface vessel in this invention;

[0044] Figure 3 This is a schematic diagram of the outer loop tracking error in the path tracking of this invention;

[0045] Figure 4This is a schematic diagram of the inner loop tracking error in the path tracking of the present invention, where (a) is an angular velocity error image; and (b) is a forward velocity error image.

[0046] Figure 5 This is a schematic diagram of the motion trajectory for path tracking in this invention. Detailed Implementation

[0047] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0048] It should be noted that the following detailed description is exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0049] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0050] Terminology Explanation:

[0051] Unmanned surface vessels (USVs): These are unmanned marine robotic platforms that navigate and operate on the water surface without a crew, using either remote control or autonomous operation. They typically employ a hull structure, propellers, and rudders for maneuverability control, and are characterized by high autonomy, high maneuverability, long endurance, and reusability. They are primarily used in marine surveying, environmental monitoring, search and rescue, and military security. As early as 1898, Nikola Tesla's invention of the "remotely piloted automated boat" is considered the world's earliest prototype of an unmanned surface vessel.

[0052] A novel hybrid controller based on pulse correction: This controller combines continuous feedback control with discrete pulse control. It consists of a lightweight continuous adaptive control law and a pulse state correction law that triggers only at discrete pulse moments. The continuous control law maintains the system's basic performance and eliminates model uncertainties, while the pulse correction law provides instantaneous and powerful adjustments to the system state at preset discrete moments to quickly suppress tracking errors. This design significantly reduces control energy consumption and actuator wear while ensuring system input-state stability by replacing high-energy-consuming continuous high-gain feedback with sparse pulse action.

[0053] The outer-loop error model refers to the dynamic system used to describe the deviation between the actual position and attitude of an unmanned surface vessel (USV) and the desired path defined by virtual guide points. The system's state variables typically include lateral tracking error, longitudinal tracking error, and heading angle error; its dynamic characteristics are jointly determined by the hull's kinematic model and the motion laws of the virtual points. The design goal of the outer-loop controller is to generate desired velocity commands to drive the error system to converge to a small neighborhood of the origin, thereby achieving accurate path tracking.

[0054] Inner-loop error model: This refers to the dynamic system used to describe the deviation between the actual speed (e.g., forward speed, yaw rate) of an unmanned surface vessel and the desired speed command generated by the outer-loop controller. The dynamic characteristics of this system are dominated by the dynamic model, which includes unknown nonlinear hydrodynamic terms. The design goal of the inner-loop controller is to generate thrust and torque by integrating continuous adaptive control with discrete pulse correction control, thereby overcoming model uncertainties and forcing the speed error system to achieve input-to-state stability.

[0055] Example 1

[0056] To further reduce the control cost of path tracking control, this embodiment provides a path tracking control method for unmanned surface vessels based on pulse correction. In complex and unknown water environments, this pulse correction-based path tracking control strategy effectively reduces the control cost of unmanned surface vessel path tracking. Figure 2 As shown, the specific steps include:

[0057] S1: Based on the underactuated characteristics of unmanned surface vessels, establish kinematic and dynamic models.

[0058] In step S1, firstly, based on the motion environment of the unmanned surface vessel (USV), an inertial coordinate system and a body coordinate system are established to obtain the position information (position coordinates) and velocity information of the USV in the inertial coordinate system; then, based on the basic kinematic laws of USV and the transformation relationship between coordinate systems, a kinematic model of the USV is established; finally, based on hydrodynamics, the underactuated characteristics of USV, and the differential propulsion principle of USV, a dynamic model of the USV is established.

[0059] like Figure 1 The schematic diagram of the movement of the unmanned surface vessel shown is illustrated below. The specific process of step S1 is as follows:

[0060] First, based on reasonable assumptions about the physical environment of the unmanned surface vessel, an inertial coordinate system is established. ;in, Represents the origin of the inertial coordinate system. Representing the inertial coordinate system axis, The y-axis represents the inertial coordinate system.

[0061] Establish the body coordinate system based on the current status of the unmanned surface vessel. ;in, This represents the origin of the body coordinate system, i.e., the center of mass of the unmanned surface vessel. Representing the body coordinate system axis, This represents the y-axis of the body coordinate system.

[0062] Then, based on the transformation relationship between the inertial coordinate system and the body coordinate system, the kinematic model of the unmanned surface vessel can be obtained in the inertial coordinate system, expressed as:

[0063] ;

[0064] ;

[0065] ;

[0066] in, , These are the coordinates of the unmanned surface vessel in the inertial coordinate system. The yaw angle of the unmanned surface vessel. , , They are respectively , , The derivative with respect to time, , , These represent the forward speed, sway speed, and yaw rate of the unmanned surface vessel in the body coordinate system.

[0067] Finally, unmanned surface vessels (USVs) typically exhibit underactuated characteristics, meaning they lack direct control input for yaw velocity. Therefore, considering only the forward velocity and yaw rate as control inputs, and taking into account the complex surface environment, we can derive the dynamic model of the USV, expressed as:

[0068] ;

[0069] ;

[0070] ;

[0071] in, , , The total mass includes both rigid body mass and hydrodynamically added mass. , , This is the corresponding hydrodynamic damping coefficient. , These are the control inputs for the forward direction and yaw rate, respectively.

[0072] S2: Obtain the desired path trajectory and the position information of the unmanned surface vessel, and construct the outer loop error model of the unmanned surface vessel in combination with the kinematic model; based on the outer loop error model, design a guidance law including the guiding velocity of the virtual leader point and the desired yaw rate, and obtain the desired forward speed.

[0073] In step S2, firstly, a Serret-Frenet coordinate system and a track coordinate system are established based on the desired path trajectory; then, based on the curvature characteristics of the desired path trajectory, the kinematic model of the unmanned surface vessel (USV), and the current position of the USV, the kinematic model of the USV in the inertial coordinate system is transformed to the Serret-Frenet coordinate system; finally, the positional error between the USV and the virtual leader point is calculated in the Serret-Frenet coordinate system, and the outer loop error model of the USV is established.

[0074] The specific process of step S2 is as follows:

[0075] First, establish the Serret-Frenet coordinate system based on the obtained expected path trajectory. ;in, This represents the origin of the Serret-Frenet coordinate system. Represents the x-axis of the Serret-Frenet coordinate system. This represents the y-axis of the Serret-Frenet coordinate system.

[0076] Establish a trajectory coordinate system based on the current motion status of the unmanned surface vessel. ;,in This represents the origin of the trajectory coordinate system, i.e., the center of mass of the unmanned surface vessel. The x-axis represents the coordinate system of the track. The y-axis represents the coordinate system of the track.

[0077] Then, record ( ( ) represents the coordinates of the virtual leader point in the inertial coordinate system. The yaw angle representing the virtual leader point can be used to establish the error in the inertial coordinate system. , ;in, This refers to the error in the X-axis direction. This refers to the error in the Y-axis direction. Let the coordinates of the unmanned surface vessel be ; assume the drift angle is . Then the yaw angle error can be expressed as Therefore, the rotation matrix of the coordinate system transformation can be expressed as:

[0078] ;

[0079] Based on the aforementioned rotation matrix, the kinematic model of the unmanned surface vessel in the inertial coordinate system is transformed to the Serret-Frenet coordinate system, as follows:

[0080] ;

[0081] in, This represents the velocity in the track coordinate system. This represents the position error vector between the unmanned surface vessel and the virtual leader point in the Serret-Frenet coordinate system. This represents the yaw rate of the virtual leader point; where s is the arc length parameter of the desired trajectory. Let be the curvature of the desired trajectory at s.

[0082] Finally, expanding the equations yields the outer-loop error model of the unmanned surface vessel, expressed as:

[0083] ;

[0084] ;

[0085] ;

[0086] in, , , These are the derivatives of the X-axis direction error, the Y-axis direction error, and the yaw angle error, respectively. The resultant velocity of the unmanned surface vessel.

[0087] In step S2, based on the outer loop error model, a guidance law is designed that includes the guiding velocity of the virtual leader point and the desired yaw rate, and the desired forward speed is specified.

[0088] The error between the forward speed and the desired forward speed of the unmanned surface vessel (USV) is calculated in the Serret-Frenet coordinate system. The error between the yaw rate and the desired yaw rate is also calculated. Based on the outer loop error model, a guidance speed and desired yaw rate including a virtual leader point are designed. The specific process is as follows:

[0089] Define the forward speed error as , ;in , These are the forward speed and yaw rate of the unmanned surface vessel, respectively. , These are the expected forward speed and the expected yaw rate, respectively. Therefore, the outer loop error model can be rewritten as:

[0090] ;

[0091] ;

[0092] ;

[0093] The designed guidance law (the guiding velocity of the virtual leader point and the desired yaw rate) is as follows:

[0094]

[0095] in, The speed of guidance for virtual leadership points. For the desired yaw rate, For virtual yaw angle parameters, , These are control parameters. Angular velocity is an auxiliary parameter, and Defined as:

[0096]

[0097] in, These are control parameters.

[0098] S3: Obtain the current forward speed and yaw rate of the unmanned surface vessel (USV). Combine the dynamic model, desired forward speed, and desired yaw rate to construct the inner loop error model of the USV. Based on the inner loop error model, establish a pulse-corrected controller to achieve path tracking of the USV.

[0099] In step S3, an inner-loop error model of the unmanned surface vessel is established based on the dynamic model of the unmanned surface vessel, the current forward speed and yaw rate of the unmanned surface vessel, and the desired forward speed and desired yaw rate.

[0100] The specific process is as follows:

[0101] To simplify the dynamic model of the unmanned surface vessel, the following function can be assumed:

[0102]

[0103] Based on the dynamic model of the unmanned surface vessel (USV), the inner-loop error model of the USV is constructed as follows:

[0104] ;

[0105] ;

[0106] in, , For nonlinear hydrodynamic unknown functions, , These are forward speed error and yaw angle error, respectively. , These are the desired forward speed and the desired yaw rate, respectively. , The total mass includes both rigid body mass and hydrodynamically added mass. , These are the control inputs for the forward direction and yaw rate, respectively.

[0107] In step S3, when establishing a controller based on pulse correction, the adaptive law estimation is first performed on the nonlinear hydrodynamic unknown function. The adaptive law estimation is specifically as follows: first, the basis function decomposition of the nonlinear hydrodynamic unknown function is performed, then the estimator is introduced, and finally the adaptive law is designed.

[0108] The specific process is as follows:

[0109] by Taking the function as an example, for the unknown function in nonlinear hydrodynamics ( By performing basis function decomposition, we can obtain the following results:

[0110]

[0111] The definitions are as follows:

[0112]

[0113] in, To estimate the unknown function, , , They are respectively, , They are respectively, for, for, for.

[0114] Introducing estimators The adaptive law is designed as follows:

[0115] ;

[0116] in, For auxiliary functions, For the basis function vector, For adaptive parameters;

[0117] Defined as:

[0118] ;

[0119] in, For pulse parameters, , For the pulse moment, This represents the number of pulses.

[0120] Based on the adaptive law, pulse gain and pulse timing sequence are designed, and a pulse correction-based controller is established to achieve the tracking of the desired forward speed and desired yaw rate under the input-state stability framework.

[0121] The design of a path tracking controller based on pulse correction is as follows:

[0122] ;

[0123] in, Represents the Dirac impulse function. Indicates pulse gain. Represents the estimated value of the unknown function. This represents the pulse time sequence. Under the guidance law and this controller, the unmanned surface vessel can achieve path tracking within an input-state stability framework if the following conditions are met:

[0124]

[0125] The following proves this conclusion:

[0126] The proof consists of two parts:

[0127] First, it is proven that input-state stability of the outer-loop error system can be achieved under the guidance law. Consider the following Lyapunov function:

[0128] ;

[0129] for You can get

[0130] ;

[0131] when When, the following inequality holds:

[0132] ;

[0133] in On the other hand, when When, the following inequality holds:

[0134] ;

[0135] in By combining the two inequalities, it can be proven that the outer loop error system is input-state stable.

[0136] Part Two:

[0137] Take the following Lyapunov function:

[0138] ;

[0139] when At that time, we can obtain:

[0140] ;

[0141] when Then:

[0142] ;

[0143] definition , ;when Sometimes:

[0144] ;

[0145] Discuss separately External interference The relationship with the impulse control action proves the input-state stability of the inner-loop error system. Combining the input-state stability of the inner-loop and outer-loop error models, it can be proven that their cascaded system is also input-state stable. Therefore, under the input-state stability framework, unmanned surface vessels can achieve path tracking. Based on the input-state stability framework, the input-state stability of the outer-loop and inner-loop error systems is achieved using guidance and control laws respectively. Note that the outer-loop and inner-loop error systems together constitute a cascaded system. Based on the input-state stability characteristics of cascaded systems, the overall input-state stability of the cascaded system is guaranteed.

[0146] The following is based on the target trajectory Initial coordinates of the unmanned surface vessel Taking an example, this paper further illustrates the effectiveness of the pulse-corrected path tracking control method for unmanned surface vessels described in this example. Table 1 shows the inner and outer loop error data under the pulse-corrected path tracking control method for unmanned surface vessels. It can be seen that both the inner and outer loop errors of the system converge to bounded quantities. The results show that the pulse-corrected path tracking control method for unmanned surface vessels in this embodiment can effectively achieve path tracking of unmanned surface vessels.

[0147]

[0148]

[0149]

[0150]

[0151]

[0152]

[0153] Example 2

[0154] This embodiment provides a path tracking control system for unmanned surface vessels based on pulse correction, including the following modules:

[0155] The kinematics and dynamics model building module is configured to: establish kinematic and dynamic models based on the underactuated characteristics of unmanned surface vessels;

[0156] The guidance module is configured to: acquire the desired path trajectory and the position information of the unmanned surface vessel, and construct the outer loop error model of the unmanned surface vessel in combination with the kinematic model; and design a guidance law including the guidance velocity of the virtual leader point and the desired yaw rate based on the outer loop error model, and specify the desired forward speed.

[0157] The pulse-correction-based control module is configured to: acquire the current forward speed and yaw rate of the unmanned surface vessel, and construct an inner-loop error model of the unmanned surface vessel by combining the dynamic model, the desired forward speed, and the desired yaw rate; and establish a pulse-correction-based controller based on the inner-loop error model to realize path tracking of the unmanned surface vessel.

[0158] It should be noted that the above modules correspond to the steps in Embodiment 1, and the examples and application scenarios implemented by the above modules and their corresponding steps are the same, but are not limited to the content disclosed in Embodiment 1. It should also be noted that the above modules can be executed in a computer system as part of the system.

[0159] In further embodiments, the following is also provided:

[0160] An electronic device includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the method described in Embodiment 1. For brevity, further details are omitted here.

[0161] It should be understood that in this embodiment, the processor can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

[0162] A computer-readable storage medium for storing computer instructions that, when executed by a processor, perform the method of Embodiment 1.

[0163] The method in Example 1 can be directly executed by a hardware processor, or it can be executed by a combination of hardware and software modules within the processor. The software modules can reside in readily available storage media in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, or registers. This storage medium is located in memory; the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method. To avoid repetition, a detailed description is not provided here.

[0164] A computer program product includes a computer program that, when executed by a processor, implements the method in Embodiment 1.

[0165] The present invention also provides at least one computer program product tangibly stored on a non-transitory computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions included in program modules, which execute in a device on a target real or virtual processor to perform the processes / methods described above. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc., that perform specific tasks or implement specific abstract data types. In various embodiments, the functionality of program modules can be combined or divided among program modules as needed. The machine-executable instructions for the program modules can execute within a local or distributed device. In a distributed device, the program modules can reside in both local and remote storage media.

[0166] The computer program code used to implement the methods of the present invention may be written in one or more programming languages. This computer program code may be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when executed by the computer or other programmable data processing device, the program code causes the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may be executed entirely on a computer, partially on a computer, as a stand-alone software package, partially on a computer and partially on a remote computer, or entirely on a remote computer or server.

[0167] In the context of this invention, computer program code or related data may be carried by any suitable carrier to enable a device, apparatus, or processor to perform the various processes and operations described above. Examples of carriers include signals, computer-readable media, and the like. Examples of signals may include electrical, optical, radio, sound, or other forms of propagation signals, such as carrier waves, infrared signals, etc.

[0168] Those skilled in the art will recognize that the units and algorithm steps described in conjunction with the embodiments herein can be implemented in electronic hardware or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0169] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A path tracking control method for unmanned surface vessels based on pulse correction, characterized in that, Includes the following steps: Based on the underactuated characteristics of unmanned surface vessels, kinematic and dynamic models are established. Obtain the desired path trajectory and the position information of the unmanned surface vessel, and construct the outer loop error model of the unmanned surface vessel in combination with the kinematic model. Based on the outer loop error model, a guidance law is designed that includes the guiding velocity of the virtual leader point and the desired yaw rate, and the desired forward velocity is specified. The specific method for constructing the outer loop error model of unmanned surface vessels is as follows: First, a Serret-Frenet coordinate system and a track coordinate system are established based on the obtained desired path trajectory. Then, based on the curvature characteristics of the desired path trajectory, the kinematic model, and the position information of the unmanned surface vessel (USV), the kinematic model of the USV in the inertial coordinate system is transformed to the Serret-Frenet coordinate system. Finally, in the Serret-Frenet coordinate system, the position error between the USV and the virtual leader point is calculated, and the outer loop error model of the USV is established. Obtain the current forward speed and yaw rate of the unmanned surface vessel, and construct the inner loop error model of the unmanned surface vessel by combining the dynamic model, the desired forward speed and the desired yaw rate. A controller based on pulse correction is established according to the inner loop error model to realize path tracking of unmanned surface vessels. When establishing a pulse correction-based controller, the nonlinear hydrodynamic unknown function is first estimated by an adaptive law. The adaptive law estimation is specifically as follows: first, the nonlinear hydrodynamic unknown function is decomposed into basis functions, then an estimator is introduced, and finally an adaptive law is designed. The pulse correction controller triggers a strong adjustment only at a preset discrete time, replacing the high-energy-consuming continuous control with sparse pulse action, thereby reducing the control energy consumption and computational burden in the path tracking process.

2. The path tracking control method for unmanned surface vessels based on pulse correction as described in claim 1, characterized in that, The kinematic model is represented as follows: ; ; ; in, , These are the coordinates of the unmanned surface vessel in the inertial coordinate system. The yaw angle of the unmanned surface vessel. , , They are respectively , , The derivative with respect to time, , , These represent the forward speed, sway speed, and yaw rate of the unmanned surface vessel in the body coordinate system.

3. The path tracking control method for unmanned surface vessels based on pulse correction as described in claim 1, characterized in that, The dynamic model is expressed as follows: ; ; ; in, , , The total mass includes both rigid body mass and hydrodynamically added mass. , , This is the corresponding hydrodynamic damping coefficient. , These are the control inputs for the forward direction and yaw rate, respectively.

4. The path tracking control method for unmanned surface vessels based on pulse correction as described in claim 1, characterized in that, The inner-loop error model for constructing unmanned surface vessels is expressed as follows: ; ; in, , For nonlinear hydrodynamic unknown functions, , These are forward speed error and yaw angle error, respectively. , These are the desired forward speed and the desired yaw rate, respectively. , The total mass includes both rigid body mass and hydrodynamically added mass. , These are the control inputs for the forward direction and yaw rate, respectively.

5. A path tracking control system for unmanned surface vessels based on pulse correction, employing the method described in claim 1, characterized in that, Includes the following modules: The kinematics and dynamics model building module is configured to: establish kinematic and dynamic models based on the underactuated characteristics of unmanned surface vessels; The guidance module is configured to: acquire the desired path trajectory and the position information of the unmanned surface vessel, and combine the kinematic model to construct the outer loop error model of the unmanned surface vessel; Based on the outer loop error model, a guidance law is designed that includes the guiding velocity of the virtual leader point and the desired yaw rate, and the desired forward velocity is specified. The pulse-correction-based control module is configured to: acquire the current forward speed and yaw rate of the unmanned surface vessel, and construct an inner-loop error model of the unmanned surface vessel by combining the dynamic model, the desired forward speed, and the desired yaw rate; and establish a pulse-correction-based controller based on the inner-loop error model to realize path tracking of the unmanned surface vessel.

6. An electronic device, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the pulse-corrected path tracking control method for unmanned surface vessels as described in any one of claims 1-4.

7. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, complete the path tracking control method for an unmanned surface vessel based on pulse correction as described in any one of claims 1-4.

8. A computer program product, characterized in that, The system includes a computer program that, when executed by a processor, implements the pulse-corrected path tracking control method for unmanned surface vessels as described in any one of claims 1-4.

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