Iterative Control of Piezoactuator for Evaluating Biomimetic, Cilia-Based Micromixing

This paper evaluates the use of different excitation waveforms to improve biomimetic-cilia-based mixing in microfluidic applications. A challenge in such studies is that, at high frequencies, vibrations in the piezoactuator can distort the achieved excitation waveform. An iterative approach is used in this work to account for the vibrational dynamics and avoid unwanted vibrations in the achieved excitation waveforms, and thereby enable the evaluation of different excitation waveforms on mixing. The main contribution of this study is to use these controlled, excitation waveforms for showing that: 1) mixing time is substantially reduced by more than an order of magnitude with the use of cilia when compared to the case without cilia, and 2) mixing time with cilia can be further reduced, by more than half, by using an asymmetric excitation waveform when compared to symmetric sinusoidal excitation.