L1 adaptive controller for unmanned surface vehicle type monohull LSS01 autopilot system and guidance design

The control technology grows rapidly at present, especially in the field of autonomous vehicles. This research presents the application of an L1 adaptive controller to an autopilot system and guidance design for an Unmanned Surface Vehicle (USV). The purpose of the L1 adaptive controller deals with how the adaptive control technology solve the problems related to the performance, robustness, and the time adaptability in the issues of uncertainty conditions. The dynamic behaviors of the USV are modeled with 3 degrees of freedom movement in the planar field, where disturbances are applied onto the system. The parameter values of the vessel will be inserted into the state space dynamic equation. The transient response behavior of the system will be analyzed to show the vessel's movement through the desired waypoints. The L1 adaptive controller method has a fast adaptation rate without losing robustness, which provides better stability using Lyapunov analysis and abilities to dampening the high-frequency as the disturbance by adding Low Pass Filter (LPF) on the control law architecture. Besides this, the L1 adaptive control is relatively simple and easy for industrial implementation. The results show the effectiveness of the L1 adaptive controller when applied to the USV guidance system.