“…2 The asymmetric motion of each cilium has a whip-like shape with an effective stroke when the cilium beats more straight and a recovery stroke when the cilium beats more close to the body surface. 7 Inspired by the impressive functionalities of biological cilia, researchers have been exploring the capabilities of artificial cilia in applications such as microrobots, 8,9 microsensors, 10,11 light, droplet and particle manipulation, 12,13 self-cleaning and antifouling surfaces, [14][15][16] microfluidic mixing, 17 and predominantly, microfluidic pumping as integrated on-chip actuators in microfluidic devices. 18 Most of the studies on artificial cilia for microfluidic pumping, including our own work, have focused on synchronous motion of artificial cilia, [19][20][21][22][23][24][25] where the artificial cilia perform a three-dimensional tilted conical motion.…”