A method and system for preset time control of unmanned surface vehicle under matched and unmatched interference

Abstract

The application discloses a kind of matching and mismatched interference under unmanned ship preset time control method and system, comprising the following steps: establishing the nonlinear motion model of unmanned ship under matching and mismatched interference;Design preset time adjustment function, the dynamic evolution process of system error is regulated;Kinematic disturbance observer and dynamics disturbance observer are designed to online estimate matching interference and mismatched interference;According to interference estimation information, construct kinematic controller, filter and dynamics controller, realize the robust preset time tracking control of reference trajectory of unmanned ship.The method proposed in the application can realize the online observation and compensation of multi-source disturbance, ensure that the system tracking error and disturbance observation error converge within the preset time, and the convergence time is adjustable, while having the advantages of continuous smooth control input, strong anti-interference ability and high engineering realizability, which can improve the control performance and reliability of unmanned ship in complex sea conditions and time-sensitive tasks.

Description

Technical Field

[0001] This invention belongs to the field of unmanned surface vessel (USV) control technology, and particularly relates to a method and system for preset time control of USVs under matched and mismatched interference. Background Technology

[0002] In recent years, with the rapid development of marine intelligent equipment and unmanned systems technology, unmanned surface vessels (USVs) have been widely used in marine environmental monitoring, maritime search and rescue, resource exploration, military reconnaissance, and maritime operational support. When USVs perform autonomous missions in complex marine environments, their motion control systems not only need high-precision trajectory tracking capabilities but also need to achieve state convergence within strict time constraints to meet the requirements of task scheduling, collaborative operations, and critical operation timing control. In typical application scenarios such as multi-vessel collaboration, high-dynamic obstacle avoidance, and task segment switching, whether the control system can guide the USV to the desired trajectory within a predetermined time directly affects the overall task chain's efficiency and operational safety. If the USV fails to achieve trajectory convergence within the specified time, it may lead to collaboration failure, task conflicts, or missed critical operational windows, thereby affecting the stable operation of the system.

[0003] However, unmanned surface vessel (USV) systems are characterized by significant nonlinearity, strong coupling, and susceptibility to external disturbances, making their motion control highly complex. On one hand, USVs are susceptible to multi-source external disturbances in complex marine environments such as wind, waves, and currents. On the other hand, USV control primarily focuses on position and heading, typically using a three-degree-of-freedom (sway, roll, and pitch) model for controller design. However, the actual motion of a USV is that of a six-degree-of-freedom system. During the reduction from a six-degree-of-freedom model to a three-degree-of-freedom model, the neglected roll, pitch, and heave motions influence the horizontal plane motion through kinematic coupling, creating mismatched disturbances that do not act through the control input channel. Especially under high-frequency maneuvering or high sea state conditions, the vertical plane coupling motion becomes more significant, and its impact on the system's motion characteristics cannot be ignored.

[0004] For the unmanned surface vessel (USV) trajectory tracking problem, existing research mainly focuses on improving system robustness and disturbance rejection performance. However, most methods are designed primarily for matched disturbances, with insufficient consideration given to the impact of mismatched disturbances. Regarding time performance, traditional asymptotically stable control methods can only guarantee that the error approaches zero within an infinite time frame, which is insufficient to meet the requirements of practical tasks with explicit time constraints. While finite-time control can achieve finite-time convergence, its convergence time depends on the initial state of the system, making it difficult to set precisely during the task planning phase. Fixed-time control eliminates the dependence on initial conditions, but its upper bound on the convergence time is usually determined by multiple control parameters, lacking a direct and clear correspondence between parameters and convergence time, thus limiting adjustability and predictability in engineering applications. Furthermore, while existing preset-time control methods can set the convergence time through parameters, they often suffer from overly conservative convergence time estimates, hindering further improvements in system dynamic performance.

[0005] Therefore, in complex marine environments, designing an unmanned surface vessel trajectory tracking and control method with adjustable convergence time, high-precision disturbance estimation capability, and good robustness while simultaneously considering the effects of matched and mismatched disturbances remains a key technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a method and system for preset time control of unmanned surface vessels under matched and unmatched interference.

[0007] The first aspect of the present invention provides a method for preset time control of unmanned surface vessels under matched and mismatched disturbances, the method comprising the following steps:

[0008] S1. Based on the kinematic and dynamic characteristics of the unmanned surface vessel (USV) and considering the impact of marine environmental disturbances, establish a nonlinear motion mathematical model of the USV under matched and unmatched disturbances.

[0009] S2, Design a preset time adjustment function To regulate the dynamic evolution of system errors;

[0010] S3, based on the established motion model of the unmanned surface vessel, integrates the designed preset time adjustment function. Kinematic and dynamic disturbance observers were designed to detect mismatched disturbances. and matching interference Make an estimate;

[0011] S4, based on interference estimation information and Combined with preset time adjustment function Constructing a kinematic controller ,filter and dynamic controller This enables robust preset time tracking control of the unmanned surface vessel for a reference trajectory.

[0012] A second aspect of the present invention provides a preset time control system for unmanned surface vessels under matched and mismatched disturbances, the system comprising:

[0013] The model building module is used to analyze the motion mechanism and environmental disturbance effects of unmanned surface vessels (USVs) and to establish nonlinear motion mathematical models of USVs under matched and unmatched disturbances.

[0014] The preset time adjustment module is used to design a preset time function to regulate the dynamic evolution of system errors;

[0015] The interference estimation module is used to design an interference observer for online estimation of mismatched and matched interference.

[0016] The tracking control module is used to construct kinematic controllers, filters, and dynamic controllers to achieve robust preset-time tracking control of the unmanned surface vessel to the reference trajectory.

[0017] A third aspect of the invention provides a computer-readable storage medium.

[0018] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps in the pre-set time control method for unmanned surface vessels under matched and mismatched interference as described above.

[0019] A fourth aspect of the present invention provides a computer device.

[0020] A computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps in the pre-set time control method for unmanned surface vessels under matched and mismatched interference as described above.

[0021] The unmanned surface vessel preset time control method under matched and mismatched interference described in this invention, compared with the prior art, has the following technical effects:

[0022] First, this invention addresses the matching and mismatched disturbance problems of unmanned surface vessels (USVs) in complex marine environments, especially the mismatched disturbances caused by the coupling effects of roll, pitch, and heave during the process of reducing the order of a six-degree-of-freedom model to a three-degree-of-freedom model. It designs a corresponding disturbance observation and compensation mechanism, realizing real-time and accurate estimation and feedforward compensation of multi-source disturbances. This breaks through the limitation of traditional control methods that are only designed for matching disturbances, and significantly improves the anti-interference capability and control robustness of USVs in complex sea states and high dynamic operating conditions.

[0023] Secondly, the preset time control method proposed in this invention enables the tracking error and disturbance observation error of the system to converge to the desired range within a preset time. Moreover, the convergence time is independent of the initial state of the system and can be intuitively adjusted through control parameters. This effectively overcomes the problems of unpredictable or difficult-to-adjust convergence time in traditional asymptotic control, finite time control and fixed time control, and significantly improves the control performance and mission reachability of unmanned surface vessels in time-sensitive tasks.

[0024] Third, this invention uses a continuous, smooth, and bounded preset time adjustment function to construct the control law, replacing the traditional discontinuous control method that relies on symbolic functions. While ensuring the convergence performance of the preset time, it effectively avoids problems such as control input chattering, singularity, and actuator saturation, thereby improving the stability and engineering feasibility of the control system and enhancing its application value in actual unmanned surface vessel systems. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a flowchart of the preset time control method for unmanned surface vessels provided in an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of the preset time control principle of the unmanned surface vessel provided in the embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of unmanned surface vessel trajectory tracking under different expected convergence times provided in the embodiments of the present invention;

[0029] Figure 4 This is a graph showing the tracking error of the unmanned surface vessel under different expected convergence times, provided by an embodiment of the present invention.

[0030] Figure 5 This is a graph showing the kinematic perturbation estimation error of an unmanned surface vessel under different expected convergence times, provided by an embodiment of the present invention.

[0031] Figure 6 This is a graph showing the estimation error of unmanned surface vessel dynamics perturbation under different expected convergence times provided in the embodiments of the present invention;

[0032] Figure 7 This is a graph showing the control input curves of an unmanned surface vessel under different expected convergence times, provided by an embodiment of the present invention. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0034] To address the problems existing in the prior art, the present invention provides a method and system for preset time control of unmanned surface vessels under matched and unmatched interference. The present invention will be described in detail below with reference to the accompanying drawings.

[0035] I. Explanatory and Illustrative Embodiments. To enable those skilled in the art to fully understand how the present invention is specifically implemented, this section provides an explanatory and illustrative description of the embodiments described in the claims.

[0036] like Figure 1 As shown, the unmanned surface vessel preset time control method under matched and mismatched interference provided in this embodiment of the invention includes the following steps:

[0037] S1. Based on the kinematic and dynamic characteristics of the unmanned surface vessel (USV) and considering the impact of marine environmental disturbances, establish a nonlinear motion mathematical model of the USV under matched and unmatched disturbances.

[0038] S2, Design a preset time adjustment function To regulate the dynamic evolution of system errors;

[0039] S3, based on the established motion model of the unmanned surface vessel, integrates the designed preset time adjustment function. Kinematic and dynamic disturbance observers were designed to detect mismatched disturbances. and matching interference Make an estimate;

[0040] S4, based on interference estimation information and Combined with preset time adjustment function Constructing a kinematic controller ,filter and dynamic controller This enables robust preset time tracking control of the unmanned surface vessel for a reference trajectory.

[0041] Figure 2 This is a schematic diagram of the preset time control principle for unmanned surface vessels under matched and mismatched interference provided in an embodiment of the present invention.

[0042] Specifically:

[0043] In step S1, considering the coupled motion effects of roll, pitch, and heave, as well as the influence of environmental disturbances, the following nonlinear motion mathematical models of the unmanned surface vessel under matched and unmatched disturbances are established:

[0044] (1)

[0045] In the formula, Location of the unmanned surface vessel and heading angle vector, Let V be the velocity vector of the unmanned surface vessel. This is the control input vector for the unmanned surface vessel. Let be the rotation matrix from the submarine system to the inertial frame. Here is the mass inertia matrix. The matrix represents the Coriolis force and the centripetal force. For hydrodynamic damping matrix, and These are the mismatch and match perturbation terms, respectively; for positive constants... and ,exist and .

[0046] In step S2, a preset time adjustment function is used. Designed as follows:

[0047] (2)

[0048] In the formula, To preset the convergence time, It is a constant.

[0049] In step S3, the kinematic disturbance observer and the dynamic disturbance observer are designed as follows:

[0050] (3)

[0051] (4)

[0052] In the formula, and These are the estimated values ​​for mismatched interference and matched interference, respectively. and These are the observer states, This is the observer gain.

[0053] In step S4, a kinematic controller is constructed. ,filter and dynamic controller To achieve robust preset time tracking control of unmanned surface vessels, the following are included:

[0054] To ensure that the unmanned surface tracking error converges within a preset time, the kinematic controller... Designed as follows:

[0055] (5)

[0056] In the formula, For position tracking error, For reference trajectory, For the derivative of the reference trajectory, and To control the gain;

[0057] To avoid the computational complexity caused by backstepping control design, a first-order preset time filter is introduced for the kinematic controller. Processing:

[0058] (6)

[0059] In the formula, and Design parameters for the filter. This is the input for filter control;

[0060] To ensure that the unmanned surface velocity tracking error converges within a preset time, the dynamic controller... Designed as follows:

[0061] (7)

[0062] In the formula, For speed tracking error, and To control the gain.

[0063] The unmanned surface vessel preset time control system under matched and mismatched interference provided in this embodiment of the invention includes:

[0064] The model building module is used to analyze the motion mechanism and environmental interference of unmanned surface vessels (USVs) and to establish nonlinear motion mathematical models of USVs under matched and unmatched interference.

[0065] The preset time adjustment module is used to design a preset time function to regulate the dynamic evolution of system errors;

[0066] The interference estimation module is used to design an interference observer for online estimation of mismatched and matched interference.

[0067] The tracking control module is used to construct kinematic controllers, filters, and dynamic controllers to achieve robust preset-time tracking control of the unmanned surface vessel to the reference trajectory.

[0068] II. Evidence of the Relevant Effects of the Embodiments. The embodiments of the present invention have achieved some positive effects during research and development or use, and indeed possess significant advantages compared to existing technologies. The following description, in conjunction with data, charts, and other materials from the experimental process, illustrates these advantages.

[0069] Simulation Experiment Verification and Analysis: To verify the performance of the pre-set time control method for unmanned surface vessels under matched and mismatched disturbances designed in this embodiment of the invention, a simulation model was established using Matlab, with the simulation time set to 60 seconds. The controller and observer parameters were set as follows: , , , , , , , , , , .

[0070] To verify the control performance of the algorithm of the present invention under different preset convergence times, the preset convergence time was set to... Second.

[0071] Figure 3 The actual and reference trajectory curves of unmanned surface vessels subjected to matched and mismatched disturbances at different expected convergence times are shown. Figure 4 The tracking error curves of the unmanned surface vessel under different expected convergence times are shown. Figure 5 The image shows the kinematic perturbation estimation error curves for the unmanned surface vessel under different expected convergence times. Figure 6 These are the dynamic perturbation estimation error curves of the unmanned surface vessel under different expected convergence times. Figure 7 These are the control input curves of the unmanned surface vessel under different expected convergence times. Figure 3 This invention demonstrates that the control method designed in this invention can drive an unmanned surface vessel (USV) to quickly and accurately track a reference trajectory under both matched and unmatched disturbances. Figure 4 This demonstrates that the control method designed in this invention can enable the position tracking error of the unmanned surface vessel to converge to a small neighborhood near zero within a preset time. Figure 5 and Figure 6 The perturbation observer designed in this invention ensures that the observation error converges to a small neighborhood near zero within a preset convergence time. Figure 7 This demonstrates that the control method designed in this invention can generate smooth and bounded control input signals.

[0072] It should be noted that embodiments of the present invention can be implemented in hardware, software, or a combination of both. The hardware portion can be implemented using dedicated logic; the software portion can be stored in memory and executed by a suitable instruction execution system, such as a microprocessor or dedicated-design hardware. Those skilled in the art will understand that the above-described devices and methods can be implemented using computer-executable instructions and / or included in processor control code, for example, such code provided on a carrier medium such as a disk, CD, or DVD-ROM, a programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The devices and modules of the present invention can be implemented by hardware circuitry such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field-programmable gate arrays, programmable logic devices, etc., or by software executed by various types of processors, or by a combination of the above-described hardware circuitry and software, such as firmware.

[0073] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method and system for preset time control of unmanned surface vessels under matched and mismatched interference, characterized in that, The following are the steps of the unmanned surface vessel (USV) preset time control method under matched and mismatched interference: S1. Based on the kinematic and dynamic characteristics of the unmanned surface vessel (USV) and considering the impact of marine environmental disturbances, establish a nonlinear motion mathematical model of the USV under matched and unmatched disturbances. S2, Design a preset time adjustment function To regulate the dynamic evolution of system errors; S3, based on the established motion model of the unmanned surface vessel, integrates the designed preset time adjustment function. Kinematic and dynamic disturbance observers were designed to detect mismatched disturbances. and matching interference Make an estimate; S4, based on interference estimation information and Combined with preset time adjustment function Constructing a kinematic controller ,filter and dynamic controller This enables robust preset time tracking control of the unmanned surface vessel for a reference trajectory.

2. The method for preset time control of unmanned surface vessels under matched and mismatched interference as described in claim 1, characterized in that, The mathematical model for the nonlinear motion of the unmanned surface vessel under matched and mismatched disturbances in step S1 is as follows: ； In the formula, Location of the unmanned surface vessel and heading angle vector, Let V be the velocity vector of the unmanned surface vessel. This is the control input vector for the unmanned surface vessel. Let be the rotation matrix from the submarine system to the inertial frame. Here is the mass inertia matrix. The matrix represents the Coriolis force and the centripetal force. For hydrodynamic damping matrix, and These are the mismatch and match perturbation terms, respectively; for positive constants... and ,exist and .

3. The method for preset time control of unmanned surface vessels under matched and mismatched interference as described in claim 1, characterized in that, The preset time adjustment function in step S2 Designed as follows: ； In the formula, To preset the convergence time, It is a constant.

4. The method for preset time control of unmanned surface vessels under matched and mismatched interference as described in claim 1, characterized in that, The kinematic perturbation observer and the dynamic perturbation observer in step S3 are designed as follows: ； ； In the formula, and These are the estimated values ​​for mismatched interference and matched interference, respectively. and These are the observer states, This is the observer gain.

5. The method for preset time control of unmanned surface vessels under matched and mismatched interference as described in claim 1, characterized in that, Kinematic controller in step S4 ,filter and dynamic controller Designed as follows: To ensure that the unmanned surface tracking error converges within a preset time, the kinematic controller... Designed as follows: ； In the formula, For position tracking error, For speed tracking error, For reference trajectory, For the derivative of the reference trajectory, and To control the gain, and Design parameters for the filter. For filter control input, and To control the gain.

6. A preset time control system for unmanned surface vessels (USVs) under matched and mismatched interference, applying the preset time control method for USVs under matched and mismatched interference as described in any one of claims 1 to 5, characterized in that, The preset time control system for unmanned surface vessels under matched and mismatched interference includes: The model building module is used to analyze the motion mechanism and environmental disturbance effects of unmanned surface vessels (USVs) and to establish nonlinear motion mathematical models of USVs under matched and unmatched disturbances. The preset time adjustment module is used to design a preset time function to regulate the dynamic evolution of system errors; The interference estimation module is used to design an interference observer for online estimation of mismatched and matched interference. The tracking control module is used to construct kinematic controllers, filters, and dynamic controllers to achieve robust preset-time tracking control of the unmanned surface vessel to the reference trajectory.

7. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor performs the steps of the preset time control method for unmanned surface vessels under matched and mismatched interference as described in any one of claims 1 to 5.

8. A computer device, characterized in that, The computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the computer program is executed by the processor, it causes the processor to perform the steps of the preset time control method for unmanned surface vessels under matched and mismatched interference as described in any one of claims 1 to 5.

Images