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Underwater maneuvering of robotic sheets through buoyancy-mediated active flutter
Junghwan Byun1,2,3, Minjo Park1,2, Sang-Min Baek1,2
1Soft Robotics Research Center, Seoul National University, Seoul, Republic of Korea.
Science Robotics
|May 27, 2021
Summary
By altering internal density, thin objects can actively control flutter for self-propulsion and underwater manipulation. This bio-inspired approach enables new possibilities for robotic locomotion and environmental remediation.
Area of Science:
- Fluid dynamics
- Robotics
- Biomimetics
Background:
- Falling leaves exhibit passive fluttering due to fluid-body coupling.
- Understanding this passive motion can inspire novel locomotion and manipulation strategies for thin, planar objects in fluids.
Purpose of the Study:
- To investigate the use of time-varying density distributions in thin, planar bodies for active flutter control and propulsion.
- To demonstrate the practical application of this principle in underwater maneuvering and environmental remediation.
Main Methods:
- Developed a 'swimming leaf' with a soft skin capable of modulating local buoyancy.
- Utilized minimal momentum control through density modulation to reorient the flutter axis.
- Demonstrated underwater maneuvering and manipulation of sheets for tasks like oil skimming.
Main Results:
- Thin, planar bodies can achieve directional propulsion by actively controlling their flutter dynamics.
- The swimming leaf demonstrated controlled reorientation and self-propulsion.
- The principle was successfully applied to adhesive and oil-skimming sheets for environmental remediation.
Conclusions:
- Active modulation of density distribution provides an effective method for controlling flutter and achieving propulsion in thin, planar objects.
- This bio-inspired approach has significant potential for developing intelligent underwater robots and advanced manipulation techniques.
- The findings offer a new perspective on locomotion and manipulation in fluid environments, with applications in environmental cleanup.
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