Model Identification and Control of a Buoyancy Change Device

• Published in: Actuators Vol. 12; no. 4; p. 180
• Main Authors: Carneiro, João Falcão, Pinto, J. Bravo, Almeida, F. Gomes de, Cruz, N. A.
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.04.2023
• Subjects: Analysis; Autonomous underwater vehicles; Buoyancy; Controllers; depth control; Dynamic characteristics; Dynamic models; Energy consumption; Energy efficiency; Modules; Ocean currents; Remote submersibles; Sovereignty; variable buoyancy systems; Vehicles; Vertical motion
• ISSN: 2076-0825; 2076-0825
• DOI: 10.3390/act12040180

There are several compelling reasons for exploring the ocean, for instance, the potential for accessing valuable resources, such as energy and minerals; establishing sovereignty; and addressing environmental issues. As a result, the scientific community has increasingly focused on the use of autonomous underwater vehicles (AUVs) for ocean exploration. Recent research has demonstrated that buoyancy change modules can greatly enhance the energy efficiency of these vehicles. However, the literature is scarce regarding the dynamic models of the vertical motion of buoyancy change modules. It is therefore difficult to develop adequate depth controllers, as this is a very complex task to perform in situ. The focus of this paper is to develop simplified linear models for a buoyancy change module that was previously designed by the authors. These models are experimentally identified and used to fine-tune depth controllers. Experimental results demonstrate that the controllers perform well, achieving a virtual zero steady-state error with satisfactory dynamic characteristics.