Fig. 3

Pattern reconfiguration of the microswarm. a The demonstration of the reversible elongation of an RPNS (Supplementary Movie 3). The green arrow shows the direction of elongation, and the red arrows show the direction of contraction. b The merging process of the two self-governed RPNSs (Supplementary Movie 4). The long axis of the RPNSs are labelled by green dashed lines, and the linking between the centres of the swarms are indicated by the red dashed line. The directions of elongation and contraction are labelled by green and red arrows, respectively. c The splitting process of an RPNS (Supplementary Movie 5). PA represents the pitch angle of the applied magnetic field. d The change in the aspect ratio with the amplitude ratio γ. e The relationship between the aspect ratio of an RPNS and time. The applied oscillation frequency is 30 Hz. The blue curve indicates the results when the amplitude ratio increases from 2 to 5; while the red curve indicates the results when the amplitude ratio increases from 3 to 5. In d and e each data point represents the average of 3 experiments. The error bar indicates the standard deviation (s.d.). The scale bar is 600 μm. f Controlled splitting of RPNSs