Interactions and\nOscillatory Dynamics of Chemically\nPowered Soft Swimmers

We report the interactions and dynamics of chemically\npowered soft\nswimmers that undergo autonomous oscillatory motion. The interaction\nof autonomous entities is the basis for the development of collective\nbehaviors among biological organisms. Collective behaviors enable\norganisms to efficiently attain food and coordinate against threats.\nThe basis of these behaviors is the interaction between nearest neighbors.\nMimicking these interactions in artificial systems would enable their\norganization for the performance of complex tasks. Oscillatory phenomena\nare also ubiquitous in nature. Hence artificial oscillatory systems\ncan serve as the most direct mimics and models of many biological\nsystems. In this work, we report the interactions and dynamics of\noscillatory swimmers propelled by the nonlinear oscillatory Belousov–Zhabotinsky\n(BZ) reaction. Individually, these swimmers displace by undergoing\nnonfully reciprocal oscillatory motion in conjunction with the BZ\nreaction. We find that, in addition to their individual oscillatory\nmotion, multiple BZ swimmers exhibit successive oscillatory changes\nin their inter swimmer distance. This oscillatory attraction and repulsion\nbetween adjacent swimmers occurs in conjunction with the BZ waves\nand oxidation state of the catalyst. The effect of swimmer size and\nnumber on these dynamic interactions is interrogated. The level of\nchemical synchronization between multiple swimmers is determined.\nThis work is a starting point for the design of collective behaviors\nutilizing autonomous chemically propelled soft swimmers.