Mobot mobot: an ocean sunfish (Mola mola) robot

Area of Science:

• Marine Biology
• Robotics
• Biomimetics

Background:

• The Ocean Sunfish (Mola mola) exhibits unique body geometry and median/paired fin (MPF) swimming.
• MPF propulsion, involving synchronized dorsal and anal fin flapping, is increasingly recognized for efficiency and agility.
• This locomotion method offers potential for developing compact and robust marine propulsion systems.

Purpose of the Study:

• To present a novel bio-inspired marine robotic platform replicating Mola mola's body and swimming strategy.
• To analyze forces generated by various flapping frequencies and patterns (synchronous and asynchronous).
• To investigate flow behavior during single flap events and continuous flapping.

Main Methods:

• Development of a Mola mola-inspired robotic test platform.
• Analysis of thrust forces generated across different flapping frequencies and patterns.
• Observation of fluid dynamics during flapping maneuvers.
• Testing of optimal flapping parameters in a free-swimming configuration.

Main Results:

• A linear relationship was observed between flapping frequency and thrust force for both synchronous and asynchronous flapping.
• Synchronous flapping generated higher thrust forces compared to asynchronous flapping at maximum obtainable frequencies.
• Free-swimming tests confirmed that synchronous flapping resulted in a larger steady-state swimming speed.

Conclusions:

• The Mola mola's median/paired fin propulsion strategy can be effectively replicated by bio-inspired robotic systems.
• Synchronous fin flapping demonstrates superior performance in generating thrust and achieving higher swimming speeds.
• This research provides a foundation for designing efficient and agile biomimetic marine propulsion.