A small variable buoyancy system for underwater vehicles

Abstract

An improved variable buoyancy system (VBS) has been developed for small underwater vehicles. This paper presents the system design, controller design and the underwater experiments. Based on the first-generation prototype, we developed a new mechanical device which has lighter weight and better waterproof performance. A PD controller combined with tracking differentiator (TD) have been adopted to achieve stable depth maintenance. Experimental results show that the improved VBS achieved a good performance. During the 120s experiment period, the VBS only moved 5mm.