Nonlinear control of autonomous underwater glider based on super-twisting sliding mode control (STSMC)

This paper presents the evaluation of super-twisting sliding mode control (STSMC) implementation in autonomous underwater glider (AUG). Underwater glider can be considered as an under-actuated system which is difficult to maneuver and it is also very much dependent on their operational environment. The nonlinear controller is designed based on nonlinear motion of equation for 1DOF internal movable sliding mass where the acceleration of internal movable sliding mass and the ballast pumping rate become the control inputs to the AUG. The controller is designed and tested for the glide path that is moving from −25° to 25°. The performance of the STSMC is compared to conventional sliding mode control (SMC) based on its response time specifications.