Fig. 2. Controlling the oscillating cells.

In this figure, some frames are accompanied by a matrix of x’s and o’s. This matrix indicates if in that given frame a motor was enabled (marked with a x) or disabled (marked with a o). a With a v-shaped opening between cells, the oscillations generated at a given cell do not propagate to neighbouring cells. This way, the BZ reaction within each cell can be individually controlled, and the user can define which cells oscillate and which cells do not oscillate. b To increase the transfer of liquid between cells, the gap between cells was fully opened. This way we achieve the objective of enabling a cell which was disabled just by enabling its surrounding cells. c Once the cells are weakly connected, they will generate coherent patterns. (Note: the oscillations in the top-left image have been contrast-enhanced, Supplementary Movie 3 shows the unedited oscillations. See Supplementary Note 1 for more details.).