Fig. 5.

(A) A bifurcated chain demonstrating tunable logic in a soft mechanical system. The distance $d_{\text{out}}$ determines the logical behavior, producing either an “and” or an “or” gate from the same system. (B) When $d_{\text{out}}$ is small (in this case, 16.7 mm), the energy barrier is higher, and both input chains must be transitioned in order for the wave to propagate through the output, comprising the function of a logical “and” gate. (C) By increasing $d_{\text{out}}$ (to 18.6 mm in this case), the energy barrier to continue propagation in the output chain decreases in a predictable manner, producing logical “or” behavior in which a transition wave in either input chain has sufficient energy to initiate propagation in the output chain.