Modeling and Simulation of Fully Actuated AUV Based on Modified ADRC

Autonomous undersea vehicles(AUVs) are nonlinear, strongly coupled, and vulnerable to external disturbances. To improve the control accuracy of AUVs, a 6-degree-of-freedom fully actuated AUV is modeled, and a proportional integral derivative(PID) controller and auto disturbance rejection controller(ADRC) are built. A comparative analysis reveals that the traditional ADRC has too many parameters to adjust, and the tracking speed of each link of the tracking differentiator(TD) is slow. Therefore, the Asin function is used to simplify each link of the traditional ADRC, and the structure of the TD is improved to solve the problem of slow tracking speed. The control effect of the PID and modified ADRC is simulated under the same simulation conditions. Simulation results show that the modified ADRC has higher control accuracy and stronger anti-disturbance ability than PID when the motion of a multi-freedom system is controlled.