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Self-excited valve using a flat ring tube: Application to robotics
Hiroyuki Nabae1, Eigo Kitamura1
1Department of Mechanical Engineering, Tokyo Institute of Technology, Tokyo, Japan.
Frontiers in Robotics and AI
|December 16, 2022
Summary
Researchers developed a simple, self-excited pneumatic valve using a flat ring tube (FRT) to overcome bulky systems in soft robotics. This novel valve enables self-excited oscillation for efficient actuation, demonstrating potential for locomotive soft robots.
Area of Science:
- Robotics
- Fluidics
- Materials Science
Background:
- Pneumatic actuators in soft robots often lead to complex and bulky driving systems.
- Self-excited oscillation offers a solution by generating oscillatory motion from non-oscillatory input.
- Current self-excited pneumatic actuators have limited variety, restricting their application scope.
Purpose of the Study:
- To introduce a simple, self-excited pneumatic valve utilizing a flat ring tube (FRT).
- To investigate the operational principles of the FRT-based self-excited valve.
- To analyze the influence of flow rate and FRT length on the valve's driving frequency.
Main Methods:
- The study explores the driving principle of the novel self-excited pneumatic valve.
- Experimental analysis was conducted to determine the effect of flow rate on driving frequency.
- The impact of flat ring tube (FRT) length on oscillation frequency was investigated.
Main Results:
- The self-excited valve's driving principle was elucidated.
- Flow rate and FRT length were found to influence the valve's driving frequency.
- A locomotive soft robot prototype equipped with the valve achieved a walking speed of 5.2 mm/s at a 1.5 Hz oscillation frequency.
Conclusions:
- The proposed simple, self-excited pneumatic valve using an FRT is effective for soft robotics.
- The valve's design addresses the issue of bulky driving systems in pneumatic soft robots.
- The successful demonstration in a locomotive robot highlights its practical applicability.
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