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arXiv · 2005.02968

Closed-Loop Control of a Piezo-Fluidic Amplifier

Chris Nicholls·Marko Bacic
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Abstract

Fluidic valves based on the Coand\u{a} effect are increasingly being considered for use in aerodynamic flow control applications. A limiting factor is their variation in switching time, which often precludes their use. The purpose of this paper is to demonstrate the closed-loop control of a recently developed, novel piezo-fluidic valve that reduces response time uncertainty at the expense of operating bandwidth. Use is made of the fact that a fluidic jet responds to a piezo tone by deflecting away from its steady state position. A control signal used to vary this deflection is amplitude modulated onto the piezo tone. Using only a pressure measurement from one of the device output channels, an output-based LQG regulator was designed to follow a desired reference deflection, achieving control of a 90 m/s jet. Finally, the controller's performance in terms of disturbance rejection and response time predictability is demonstrated.

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Chris Nicholls, Marko Bacic. 2020-05-06. Closed-Loop Control of a Piezo-Fluidic Amplifier. https://doi.org/10.2514/1.j059305

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