Depth control methods of variable buoyancy AUV

Autonomous Underwater Vehicles (AUVs) are widespread and effective tool for oceanographic research. The main applications of AUVs are long-term missions for survey of wide area and patrolling. However the key issue for long term cruising range is energy storage. One of approaches to reduce energy consumption is using of the variable buoyancy system (VBS) on the AUV. This approach allows to compensate AUV's buoyancy and to reduce energy on hovering due to it. Two combined depth control methods based on cooperative work of propulsion system and variable buoyancy system has been presented in this paper. Estimation of the methods based on calculation of energy consumption and transient response time has been made. Comparison of ones with methods based on standalone work of propulsion system and VBS has been made. Provided methods was proved on simulation and water pool tests on variable buoyancy AUV “CH-2” designed at Institute of Marine Technology Problems FEB RAS year ago.