Hatatani Miku, Yamamoto Daigo, Shioi Akihisa
Department of Chemical Engineering and Materials Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0321, Japan.
Sci Rep. 2024 Jul 18;14(1):16619. doi: 10.1038/s41598-024-67383-1.
A geometrically symmetric gear with asymmetric surface wettability exhibits one-way spin on a vibrating water bed. On the side face of the gear, a parafilm was coated to create asymmetry in the surface energy. The gear shows fluctuations in both directions within a shorter timescale; however, for a longer timescale, the gear exhibits a one-way spin. This unique motion is generated by a stochastic process with a biased driving force produced by the interaction between the vibrating water surface and the side face of the gear. This new model resembles an active Brownian ratchet. Until now, most ratchet motors, which obtain regular motion from nonthermal fluctuations, utilize a geometrical ratchet structure. However, in this study, the surface energy forms a ratchet that rectifies the noisy motion.
一个具有不对称表面润湿性的几何对称齿轮在振动水床上表现出单向旋转。在齿轮的侧面，涂覆了一层石蜡膜以产生表面能的不对称性。在较短的时间尺度内，齿轮在两个方向上都有波动；然而，在较长的时间尺度上，齿轮呈现单向旋转。这种独特的运动是由一个随机过程产生的，该过程具有由振动水面与齿轮侧面之间的相互作用产生的偏置驱动力。这个新模型类似于一个有源布朗棘轮。到目前为止，大多数从非热涨落中获得规则运动的棘轮电机都采用几何棘轮结构。然而，在本研究中，表面能形成了一个使噪声运动整流的棘轮。
