Abstract
A variable buoyancy system (VBS) operated by a reversible fuel cell (RFC) with feedback depth control is developed. The system varies its buoyancy by inflating or deflating a bladder via gases produced by electrolysis or consumed through fuel cells. The system has advantages in the perspective of energy efficiency since some of the energy used for the electrolysis process is recaptured by the fuel cell. Furthermore, it is noiseless and compact, facilitating smooth integration with other underwater robots requiring buoyancy control. A PDA (Proportional-Derivative-Acceleration) feedback controller is designed to regulate the electrochemical process to position and stabilize the device at a certain depth. The model describing the VBS’s motion dynamics with bounded gas rates is used to evaluate the range of motion before instability. Then, a jerk-constrained time-optimal trajectory planner is employed to generate a suboptimal trajectory to move the VBS between two known depths. Finally, the effectiveness of the controller is confirmed with experiments. The real-time experiment shows that the controller can track both sinusoidal reference and the suboptimal trajectory planned between two depths. The device can achieve fine depth control with a depth resolution of 0.06 m, which makes its application promising in bio-inspired underwater robots.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
