Underactuated USV path following mechanism based on the cascade method

Mingzhen Lin,Yandong Pang,Hongsheng Lin,Zhiqiang Zhang,Qing Ji

doi:10.1038/s41598-022-05456-9

Mingzhen Lin, Yandong Pang + Show 3 more

Open Access

https://doi.org/10.1038/s41598-022-05456-9

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Journal: Scientific Reports	Publication Date: Jan 27, 2022
Citations: 6	License type: open-access

Affiliation: Naval University of Engineering

Abstract

The path following control under disturbance was studied for an underactuated unmanned surface vehicle (USV) subject to the rudder angle and velocity constraints. For this reason, a variable look-ahead integral line-of-sight (LOS) guidance law was designed on the basis of the disturbance estimation and compensation, and a cascade path following control system was created following the heading control law based on the model prediction. Firstly, the guidance law was designed using the USV three-degree-of-freedom (DOF) motion model and the LOS method, while the tracking error state was introduced to design the real-time estimation of disturbance observer and compensate for the influence of ocean current. Moreover, the stability of the system was analyzed. Secondly, sufficient attention was paid to the rudder angle and velocity constraints and the influence of system delay and other factors in the process of path following when the heading control law was designed with the USV motion response model and the model predictive control (MPC). The moving horizon optimization strategy was adopted to achieve better dynamic performance, effectively overcome the influence of model and environmental uncertainties, and further prove the stability of the control law. Thirdly, a simulation experiment was carried out to verify the effectiveness and advancement of the proposed algorithm. Fourthly, the “Sturgeon 03” USV was used in the lake test of the proposed control algorithm to prove its feasibility in the engineering practices.

Highlights

Uniform global asymptotic stability of the system was proved[13]
In Reference[15], the influence of the complex marine environment was fully considered while designing a path following control system based on the cascade of the variable look-ahead integral LOS guidance algorithm and the adaptive sideslip compensation heading control algorithm
The control law is designed with the Unmanned surface vehicle (USV) motion response model and model predictive control (MPC) to address such problems as the instability and large error caused by the rudder angle constraint and system delay in the path following

Summary

Introduction

Uniform global asymptotic stability of the system was proved[13]. Assuming that the disturbance of ocean current was bounded and varied slowly, Fossen et al relied on the Lyapunov stability theory and the direct feedback of error to compensate for the drift angle caused by the disturbance including ocean current in a real-time manner. The control law is designed with the USV motion response model and model predictive control (MPC) to address such problems as the instability and large error caused by the rudder angle constraint and system delay in the path following. Equation (4) is transformed into the design model of USV heading controller as follows: ψ = r r where the range of USV rudder angle is δ ∈ [δmin, δmax].

Results

Conclusion