Adaptive sliding-mode path following control system of the underactuated USV under the influence of ocean currents

In this brief, the path following control problem of underactuated hovercrafts subject to nonlinear time-varying uncertainties and a safety limit constraint (SLC) is addressed. A novel homogenous nonlinear extended state observer (NESO)-based safe motion controller for a path following control scenario of underactuated hovercrafts is proposed. First, a NESO is constructed to estimate and compensate the nonlinear time-varying uncertainties for the underactuated hovercraft. Then, a NESO-based backstepping sliding mode control (BSMC) law with a turning SLC is proposed to achieve the yaw control for underactuated hovercrafts, which improves both safety and maneuverability of the underactuated hovercraft during the path following control scenario. The nonlinear time-varying turning SLC is first directly taken into the control system design, which is achieved by introducing an auxiliary dynamic system to limit the virtual input control during the backstepping design process. A NESO-based backstepping surge control law is also designed to achieve the surge control for underactuated hovercrafts. Furthermore, all error signals of the proposed closed-loop control system are proven to be bounded. Finally, an application case is tested on an underactuated hovercraft to illustrate the effectiveness and superiority of the designed control scheme.

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High-Gain Extended State Observer Based Adaptive Sliding Mode Path Following Control for An Underactuated Vessel Sailing in Restricted Waters

Applied Sciences ◽

10.3390/app9061102 ◽

2019 ◽

Vol 9 (6) ◽

pp. 1102 ◽

Cited By ~ 2

Author(s):

Jianqin Wang ◽

Zaojian Zou ◽

Tao Wang

Keyword(s):

Sliding Mode ◽

Path Following ◽

High Gain ◽

State Observer ◽

Extended State Observer ◽

Model Parameters ◽

Extended State ◽

External Disturbances ◽

Adaptive Sliding Mode ◽

Path Following Control

This paper studied the path following problem for an underactuated vessel sailing in restricted waters with varying water depths. A novel high-gain extended state observer based adaptive sliding mode path following control scheme was proposed. The high-gain extended state observer based line-of-sight guidance law was designed according to vessel kinematics in the horizontal plane, which achieved accurate guidance in spite of time-varying sideslip angles. In the guidance system, a guidance angle was calculated to serve as a reference input for the yaw tracking control system. The sliding mode yaw tracking control system was designed, which can deal with model uncertainties and external disturbances. Since it is hard to obtain the exact model parameters in advance, an adaptive technique was adopted to estimate the unknown parameters, and an adaptive sliding mode control was designed to make the yaw tracking errors globally and asymptotically converge to zero in spite of unknown model parameters, model uncertainties, and external disturbances. Furthermore, the global uniformly asymptotically stability of the closed-loop system was proven based on the cascade system theory. Lastly, simulation experiments were conducted to validate the analysis results and to demonstrate the superiority of the proposed scheme.

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Data-driven sideslip observer-based adaptive sliding-mode path-following control of underactuated marine vessels

Ocean Engineering ◽

10.1016/j.oceaneng.2019.106910 ◽

2020 ◽

Vol 197 ◽

pp. 106910 ◽

Cited By ~ 3

Author(s):

Yongpeng Weng ◽

Ning Wang ◽

Carlos Guedes Soares

Keyword(s):

Sliding Mode ◽

Path Following ◽

Data Driven ◽

Adaptive Sliding Mode ◽

Path Following Control ◽

Marine Vessels

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Modified Vector Field Path-Following Control System for an Underactuated Autonomous Surface Ship Modelin the Presence of Static Obstacles

Journal of Marine Science and Engineering ◽

10.3390/jmse9060652 ◽

2021 ◽

Vol 9 (6) ◽

pp. 652

Author(s):

Haitong Xu ◽

Miguel A. Hinostroza ◽

C. Guedes Guedes Soares

Keyword(s):

Control System ◽

Vector Field ◽

Path Following ◽

Field Method ◽

Integrated System ◽

Ship Model ◽

Surface Ship ◽

Path Following Control ◽

Exponentially Stable ◽

Vector Field Method

A modified path-following control system using the vector field method for an underactuated autonomous surface ship model is proposed in the presence of static obstacles. With this integrated system, autonomous ships are capable of following the predefined path, while avoiding the obstacles automatically. It is different from the methods in most published papers, which usually study path-following and obstacle collision avoidance, separately. This paper considers the coupled path following and collision avoidance task as a whole. Meanwhile, the paper also shows the heading control design method in the presence of static obstacles. To obtain a strong stability property, a nonlinear autopilot is designed based on the manoeuvring tests of the free-running ship model. The equilibrium point of the controller is globally exponentially stable. For the guidance system, a novel vector field method was proposed, and the proof shows the coupled guidance and control system is uniform semi-global exponentially stable (USGES). To prevent the obstacles near the predefined path, the proposed guidance law is augmented by integrating the repelling field of obstacles so that it can control the ship travel toward the predefined path through the obstacles safely. The repelling field function is given considering the obstacle shape and collision risk using the velocity obstacle (VO) algorithm. The simulations and ship model test were performed to validate the integrated system of autonomous ships.

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