In this study, we introduce research aimed at developing a compact particle-excitation flow control valve that enables continuous control of air flow rate. We have been developing a compact control valve with continuous flow control for application to soft actuators. The control valve that we are developing uses particles as a valve plug, which does not require a valve plug positioning function and allows the control valve to be miniaturized. Furthermore, by controlling the movements of the particles on the orifice, the control flow rate can be made finer and the response can be improved. On the other hand, the past driving principle used the resonant mode of an oscillator utilizing a piezoelectric element (PZT) to control the motion of the particles. In this vibration mode, the size of the oscillator limits the miniaturization. Therefore, we propose a drive method that uses simple plate deflection vibration mode. This drive method eliminates the need for a large oscillator, and thus reduces the size of the control valve. To confirm the feasibility of the proposed drive method, we fabricated a prototype and evaluated its characteristics during flow control.

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