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Published on: August 17, 2018
Electrohydraulic Folding Ring Actuators for Radially Contracting Applications
Gavril Yong En Tan1, Quan Xiong2, Jonathan William Ambrose1
1Department of Biomedical Engineering, National University of Singapore, Singapore, Singapore.
Summary
We developed a novel electrohydraulic folding ring actuator (EFRA) for soft robotics. This compact, lightweight actuator achieves high radial contraction and force output, enabling advanced robotic applications.
Area of Science:
- Robotics
- Materials Science
- Biomimetics
Background:
- Soft actuators inspired by biological circular muscles are crucial for advanced robotic functions.
- Electrohydraulic actuation offers potential for high-performance radial contraction in compact designs.
Purpose of the Study:
- To introduce and characterize a novel electrohydraulic folding ring actuator (EFRA).
- To demonstrate the EFRA's capabilities in robotic manipulation, locomotion, and artificial sphincter applications.
Main Methods:
- Design and fabrication of a compact, triangular folding ring actuator.
- Electrohydraulic actuation at 7 kV to induce radial contraction.
- Performance evaluation including contraction ratio, sustained actuation, and force output.
Main Results:
- The EFRA achieved a high contraction ratio of 0.89 sustained over 5 seconds.
- The actuator produced significant inward-directed force (∼0.96 N) relative to its low mass (∼25.9 g).
- Multiple synchronously bending segments enhanced radial contraction compared to previous designs.
Conclusions:
- The EFRA offers high performance in a lightweight and compact form factor.
- Its capabilities are suitable for diverse robotic applications requiring radial contraction.
- The folding mechanism is key to the actuator's enhanced performance.
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