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Published on: November 14, 2015
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.
Abstract:
Complex and bulky driving systems are among the main issues for soft robots driven by pneumatic actuators. Self-excited oscillation is a promising approach for dealing with this problem: oscillatory actuation is generated from non-oscillatory input. However, small varieties of self-excited pneumatic actuators currently limit their applications. We present a simple, self-excited pneumatic valve that uses a flat ring tube (FRT), a device originally developed as a self-excited pneumatic actuator. First, we explore the driving principle of the self-excited valve and investigate the effect of the flow rate and FRT length on its driving frequency. Then, a locomotive robot containing the valve is demonstrated. The prototype succeeded in walking at 5.2 mm/s when the oscillation frequency of the valve was 1.5 Hz, showing the applicability of the proposed valve to soft robotics.
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