Design and control of hybrid underwater glider

In this article, a design and analysis on 200-m-class hybrid underwater glider actuated by a buoyancy engine and a thruster was studied. The hull shape of the hybrid underwater glider was designed to reduce underwater resistance using Myring hull profile equations. A computational fluid dynamics analysis was conducted, and a resistance coefficient similar to that of existing underwater vehicle was calculated such that simulation reliability was verified. The relationship between the control value of the ballast discharged by the buoyancy engine and the velocity of a glider according to the path angle was analyzed. Through the analysis, the relationship between the optimal glide angle and the designed control value of the ballast water was drawn, and using this relationship, the optimal glider velocity was estimated. Also, the velocity of the hybrid underwater glider using the thruster only was measured through an experiment. Using both the thruster and ballast water control, it was shown that the maximum velocity of the developed hybrid underwater glider is over 2.4 knots.