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Cartilage structure increases swimming efficiency of underwater robots
Masaki Yurugi1, Makoto Shimanokami1, Toshiaki Nagai2
1Faculty of Science and Technology, Department of Mechanical Engineering, Meijo University, 1-501 Shiogamaguchi, Tempaku-ku, Nagoya, 468-8502, Japan.
Scientific Reports
|May 29, 2021
Summary
This study developed a stingray robot inspired by Rajiform swimming. Incorporating cartilage structures significantly enhanced swimming efficiency in soft underwater robots.
Area of Science:
- Robotics
- Biomimetics
- Marine Engineering
Background:
- Traditional underwater robots with propellers can harm marine ecosystems.
- Biomimetic robots offer greater environmental adaptability by mimicking aquatic animals.
- Rajiform swimming, characterized by traveling fin waves, is an efficient natural locomotion method.
Purpose of the Study:
- To investigate the role of anisotropic stiffness in Rajiform swimming.
- To develop and test a bio-inspired soft underwater robot mimicking stingray locomotion.
- To determine if cartilage structures enhance swimming efficiency in soft robots.
Main Methods:
- Developed a stingray robot using silicone-based cartilage and soft tissues.
- Fabricated control robots with varying material compositions (no cartilage, combined materials).
- Tested robot stiffness and swimming performance to evaluate efficiency.
Main Results:
- The inclusion of cartilage structures in robot fins demonstrably increased swimming efficiency.
- Anisotropic stiffness, achieved through material distribution, is crucial for efficient locomotion.
- Soft underwater robots benefit from the strategic integration of hard and soft components.
Conclusions:
- Anisotropic stiffness derived from cartilage integration is key to efficient Rajiform-inspired swimming.
- The design principles of soft aquatic animals can be applied to create high-performance underwater robots.
- Optimizing the distribution of soft and hard materials is essential for advanced soft robotics.
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