Abstract:
This thesis presents a first-principle based dynamic model for underwater gliders, capturing
key forces like hydrodynamic drag, buoyancy, added mass, and nonlinear couplings.
Designing a robust controller for underwater gliders is challenging due to their
nonlinear and under-actuated dynamics. This thesis proposes a Double Integral Finite-
Time Super-Twisting Sliding Mode Controller (DIFTST-SMC) to achieve precise trajectory
tracking and disturbance rejection in the presence of external forces. The study
focuses on the longitudinal and vertical-plane dynamics of the glider. The control strategy
combines integral sliding mode and super-twisting algorithms to ensure finite-time
convergence and minimize chattering. To enhance performance, Red Fox Optimization
(RFO) is applied to optimize the controller gains. The proposed approach is validated
using simulation data. Results demonstrate improved tracking accuracy and robustness
compared to conventional sliding mode control methods, highlighting the effectiveness
of the combined control and optimization framework.
