V3I2P10

Improving Estimation and Control Accuracy of Underwater Vehicle Dynamics Using the Extended Kalman Filter and Sliding Mode Control

Ngo Trung Toan^1* , Dao Thanh Bang¹

Abstract

This paper proposes a method that combines the Extended Kalman Filter (EKF) with Sliding Mode Control (SMC) in order to improve the accuracy of estimation and control of the dynamic parameters of a 12-degree-of-freedom (12 DOF) underwater vehicle. A complete nonlinear dynamic model of the vehicle is developed, taking into account environmental effects including ocean waves, currents, and disturbances. EKF is employed to accurately estimate position, velocity, Euler angles, and angular rates even when measurement signals are corrupted by Gaussian noise. Meanwhile, the sliding mode controller is applied to the depth and pitch control channels, in combination with a PD controller for the yaw channel, ensuring fast response and robustness against external disturbances and parameter variations. Simulation results show that the proposed method significantly reduces estimation error, maintains system stability, and limits control energy compared to traditional methods.

Keywords:

Underwater vehicle, 12 DOF, EKF, Extended Kalman Filter, SMC, Sliding Mode Control, robust control, marine environmental disturbance