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CN-121979272-A - Unmanned ship track tracking control method and system with unknown system parameters

CN121979272ACN 121979272 ACN121979272 ACN 121979272ACN-121979272-A

Abstract

The invention discloses an unmanned ship track tracking control method and system with unknown system parameters, which comprises the steps of constructing a second-order state space form containing lumped disturbance items, constructing a dynamic equation of a position error system by defining a position tracking error signal and a speed error variable, constructing the dynamic equation of the speed error system, designing continuous actual control moment output, and introducing a sensor based on the actual control moment output The method comprises the steps of correcting a robust compensation term of a mechanism, designing a self-adaptive parameter updating law with dead zone switching characteristic based on real-time tracking error dynamics of an unmanned ship, constructing a comprehensive Lyapunov function, deducing position tracking error, speed tracking error and all parameter estimation errors into consistent final bounded signals according to actual control moment output and the self-adaptive parameter updating law. The invention does not depend on accurate model parameters, has strong anti-interference capability, and can effectively inhibit the buffeting of the actuator and prevent parameter drift.

Inventors

  • JIN XIAOZHENG
  • ZHANG SHEN
  • FAN JINGWEN

Assignees

  • 齐鲁工业大学(山东省科学院)

Dates

Publication Date
20260505
Application Date
20260205

Claims (10)

  1. 1. The unmanned ship track tracking control method with unknown system parameters is characterized by comprising the following steps: constructing a dynamic equation of the unmanned ship containing all unknown parameters, and converting the dynamic equation into a second-order state space form containing lumped disturbance terms; Based on a preset bounded expected reference track, by defining a position tracking error signal and a speed error variable and combining a dynamic equation of the unmanned ship to deduce an error association relationship, designing a virtual control law to construct a dynamic equation of a position error system; constructing a radial basis function neural network to perform online approximation; based on the second-order state space form, constructing a kinetic equation of a speed error system, designing continuous actual control moment output, and introducing a second-order state space based model into the actual control moment output Correcting a robust compensation term of a mechanism; based on real-time tracking error dynamics of the unmanned ship, designing a self-adaptive parameter updating law with a dead zone switching characteristic; And constructing a comprehensive Lyapunov function, solving the time derivative of the Lyapunov function, and deducing a position tracking error, a speed tracking error and all parameter estimation errors into consistent final bounded signals according to the actual control moment output and the self-adaptive parameter update law.
  2. 2. The unmanned ship track tracking control method of claim 1, wherein the dynamic equation is converted into a second-order state space form containing lumped disturbance terms, the method comprises the steps of decomposing the totally unknown parameters into a known nominal parameter matrix and unknown deviation parameters which can be selected freely, obtaining the lumped disturbance terms and presetting boundary conditions based on the unmodeled dynamic, unknown deviation parameters and external environment interference, and finally converting the dynamic equation into the second-order state space form containing the lumped disturbance terms.
  3. 3. A method of unmanned vehicle trajectory tracking control with unknown system parameters according to claim 2, wherein the second order state space form containing lumped disturbance terms is expressed as: ; Wherein, the The position and helm direction angle of the unmanned ship under the ground coordinate system are represented, Representing a rotation matrix for converting variables between an earth-fixed inertial coordinate system and a body-fixed coordinate system, Representing the velocity vector in the body coordinate system, Representing the lumped-perturbation term(s), Representing the control input of the propeller(s), 、 All representing known nominal parameters.
  4. 4. A method of unmanned ship trajectory tracking control with unknown system parameters as claimed in claim 3, wherein the boundary conditions to be satisfied by the lumped disturbance term are: Wherein, the method comprises the steps of, In order to control the input of the relevant disturbance factor, As an unknown continuous non-linear function, The perturbation boundary constant is fixed.
  5. 5. The unmanned ship track tracking control method with unknown system parameters according to claim 1, wherein the specific method for constructing the dynamics equation of the position error system is that firstly, the position tracking error signal is defined as: And then to Obtaining time derivative by combining dynamic equation of unmanned ship Redefining the speed error variable as Wherein, the method comprises the steps of, And finally, obtaining a dynamic equation of the position error system, which is expressed as: ; Wherein, the For a preset bounded desired reference trajectory, In order to be a virtual control law, The gain matrix is positive diagonally for the position loop.
  6. 6. The unmanned ship trajectory tracking control method of claim 1, wherein the dynamics equation of the velocity error system is expressed as: ; designing a continuous actual control torque output is expressed as: Wherein, the method comprises the steps of, The gain matrix is positively determined for symmetry, Known dynamics for the compensation subsystem; 、 on-line estimation values of system matrix parameters; Is based on The robust compensation term of the correction mechanism.
  7. 7. The unmanned ship track following control method with unknown system parameters according to claim 6, wherein the unmanned ship track following control method is based on the following steps The robust compensation term for the correction mechanism is expressed as: ; Wherein, the Is a preset small positive number which is used for the treatment of the heart disease, 、 、 The real-time estimation values of the interference boundary and the network weight are respectively.
  8. 8. An unmanned ship track tracking control system with unknown system parameters, which is characterized by comprising: The dynamic modeling and disturbance aggregation module is configured to construct a dynamic equation of the unmanned ship containing all unknown parameters and convert the dynamic equation into a second-order state space form containing lumped disturbance terms; The dynamic equation construction module of the position error system is configured to design a virtual control law to construct a dynamic equation of the position error system by defining a position tracking error signal and a speed error variable and combining a dynamic equation of the unmanned ship to derive an error association relation based on a preset bounded expected reference track; The approximation module is configured to construct a radial basis function neural network for online approximation; A control output module configured to construct a kinetic equation of the speed error system based on the second-order state space form, design a continuous actual control moment output, and introduce a second-order-based control moment output Correcting a robust compensation term of a mechanism; The self-adaptive updating law design module is configured to design a self-adaptive parameter updating law with a dead zone switching characteristic based on real-time tracking error dynamic state of the unmanned ship; The Lyapunov stability proving module is configured to construct a comprehensive Lyapunov function, solve the time derivative of the Lyapunov function, derive a position tracking error, a speed tracking error and all parameter estimation errors from inequality according to the actual control moment output and the adaptive parameter update law, and are consistent final bounded signals.
  9. 9. An electronic device comprising a memory and a processor and computer instructions stored on the memory and running on the processor, which when executed by the processor, perform a method of unmanned aerial vehicle trajectory tracking control of unknown system parameters according to any one of claims 1 to 7.
  10. 10. A computer readable storage medium storing computer instructions which, when executed by a processor, perform a method of unmanned aerial vehicle trajectory tracking control of unknown system parameters of any one of claims 1 to 7.

Description

Unmanned ship track tracking control method and system with unknown system parameters Technical Field The invention relates to the technical field of unmanned ship track tracking control, in particular to an unmanned ship track tracking control method and system with unknown system parameters. Background The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art. With the continuous deep exploration and development of the ocean, the unmanned ship is used as a high-performance water surface operation platform, and has great application potential in numerous fields such as military reconnaissance, environment monitoring, marine rescue and the like. The unmanned ship dynamics characteristics conform to the second-order Euler-Lagrange system description, and the high-precision and high-stability track tracking control is realized, so that the unmanned ship dynamics characteristics are an important precondition for smoothly executing complex tasks. In practical engineering applications, unmanned boat control designs face a number of serious challenges. On one hand, the unmanned ship system has strong nonlinearity and high coupling characteristics, complex hydrodynamic coupling exists among heave, sway and bow movement, on the other hand, accurate model parameters are difficult to obtain, physical parameters such as hydrodynamic derivatives, rotational inertia and the like are difficult to accurately obtain through offline measurement, real-time offset can be caused along with load change, navigation speed fluctuation and hull abrasion, and meanwhile, unpredictable external interference such as wind, wave, flow and the like acts on the system in an additive mode in the severe operating environment of the unmanned ship, so that the stability of a closed-loop system is seriously affected. In order to solve the unmanned ship track tracking problem, the traditional calculation moment control and PID control highly depend on an accurate system model, the performance can be severely reduced when parameters fluctuate, the sliding mode control (Sliding mode Control) is widely adopted due to strong robustness to uncertainty, but the inherent buffeting phenomenon can excite the system to have unmodeled high-frequency dynamics, so that an actuator is overheated, worn and even damaged, and even if buffeting is relieved by adopting a saturation function or a boundary layer method, steady-state tracking precision is often sacrificed. The adaptive control is used as a powerful tool for processing parameter uncertainty and can estimate unknown parameters on line, but the traditional adaptive control generally requires system dynamics to meet a parameter linearization assumption, an unmanned ship damping term comprises a complex nonlinear function, accurate linearization is difficult, and under external interference, the traditional adaptive law can cause a parameter drift phenomenon, and finally the system is unstable. At present, a method for approaching unknown nonlinear dynamics by utilizing a Radial Basis Function Neural Network (RBFNN) is paid attention to, but the existing neural network control method still has obvious defects that most methods still depend on system model information partially, such as assuming that an inertia matrix is known or the boundary of the inertia matrix is known, autonomous control under the condition of unknown full parameters is difficult to realize, and meanwhile, in order to compensate approximation errors and external interference of the neural network, a robust term based on a symbol function is introduced into a control law by most methods, so that the buffeting problem is inevitably introduced again. Disclosure of Invention In order to solve the problems, the invention provides an unmanned ship track tracking control method and system with unknown system parameters, which is an advanced unmanned ship control strategy that does not depend on accurate model parameters, has strong anti-interference capability, can effectively inhibit buffeting of an actuator and prevent parameter drift, and has important theoretical significance and practical value for improving the operation capability of an unmanned ship under complex sea conditions. In order to achieve the above purpose, the present invention adopts the following technical scheme: in a first aspect, the present invention provides a method for tracking and controlling a trajectory of an unmanned ship with unknown system parameters, comprising the following steps: constructing a dynamic equation of the unmanned ship containing all unknown parameters, and converting the dynamic equation into a second-order state space form containing lumped disturbance terms; Based on a preset bounded expected reference track, by defining a position tracking error signal and a speed error variable and combining a dynamic equation of the unmanned ship to deduce an error