Autonomous Underwater Vehicle Control Using an Extended State Observer Based Adaptive Fuzzy Sliding Mode Controller

In this paper, an extended state observer (ESO)-based adaptive fuzzy sliding mode control (AFSMC) method was proposed for trajectory tracking of an autonomous underwater vehicle (AUV) operating under conditions of modeling uncertainty and external disturbances. AFSMC offers significant advantages, including reduced chattering and enhanced control performance, compared with conventional sliding mode control (SMC). However, in for large external disturbances, conventional SMC requires a higher control effort, which can exacerbate chattering and degrade control performance. To address these challenges, an ESO was introduced to compensate for external disturbances and modeling uncertainties in the AUV control system. The stability of the proposed ESO-based AFSMC was rigorously proven using Lyapunov’s stability theory. Simulation results confirm that the proposed AFSMC effectively attenuates high-frequency chattering, whereas the ESO minimizes the impact of external disturbances.