Amazing stuff!
"Now, ... researchers show that networks of flowing water and other fluids can store their own memories—similar to how a computer chip does—an innovation that could steer robots and provide insight about some simple organisms. ...
... researchers created a small chip with multiple tiny channels, each with a depth about half the width of a human hair. Inside these channels, they placed a series of flexible microfibers that stand in the way of the fluid flowing through the channels. Pressure from the flow can cause the fibers to switch between two states, affecting how the fluid passes.
This forms a “memory” of past flows, making each fiber’s current state depend on its history and, when coupled, on the states of other fibers. The two stable configurations of each fiber can represent a zero or a one, much like a bit in computer memory. ...
Computers typically store information in electronic memory devices. This study, though, demonstrates that information about past flows can also be stored in the configurations of flexible fibers, which switch passively as the imposed flow changes. ..."
From the abstract:
"Hysterons provide a minimal description of memory in driven matter: bistable elements with distinct switching thresholds whose collective dynamics generate hysteresis, avalanches, and history-dependent switching.
Experimental realizations have so far been dominated by solid-state mechanical systems, where bistability is usually encoded structurally through buckling, snap-through, or geometric incompatibility.
Here we realize hysteron physics through a hydrodynamic route. A single elastic fiber anchored in a microfluidic channel becomes bistable through nonlinear elastohydrodynamic feedback: Viscous loading deforms the fiber, deformation reshapes hydraulic resistance, and flow redistribution modifies the loading.
This feedback produces a fluidic hysteron whose onset is organized by a cusp catastrophe in geometric control parameters.
A parallel bypass channel acts as a geometric load line that reshapes, and can even eliminate, bistability while simultaneously mediating long-ranged hydraulic interactions between fibers.
In arrays, varying a single geometric parameter drives a transition from a noninteracting Preisach regime with return-point memory to an interacting regime with configuration-dependent thresholds, mixed-direction switching paths, and projected trajectories that cross the independent-Preisach envelope.
These results establish a passive hydrodynamic route to hysteron networks, in which memory emerges from flow-structure feedback and global hydraulic constraints."
Storing memory on a chip with flowing water | News | Yale Engineering
Fig. 1 Elastohydrodynamic snap-through of an anchored fiber.
