We’ve always been interested in fluidic logic and, based on [soiboi’s] videos, he is too. His latest shows how to use silicone and a vacuum to build a multiplexed dot matrix display. This is a fascinating look at how you design with air instead of electrons.

Just like a regular display, it isn’t efficient to control each element separately. Usually, it’s better to multiplex such that 16 “pixels” need only row and column air valves. Just as you might use transistors, the project uses “air transistors” to build logic gates.

Each pixel is a bit of silicone that can be sucked down only when a row and column are drawing a vacuum simultaneously. The air transistor is a similar membrane that a control input can suck down. In its relaxed position, two air channels are blocked by the membrane. When the membrane moves away, the two channels connect. This is analogous to a Field Effect Transistor (FET), where the channel conducts electricity when the gate is active and does not conduct when the gate is inactive.

We appreciated the step-by-step development. The video moves from a pixel step-by-step to small arrays and then to a 4×4 array. If this is your first encounter with fluidic logic, you can learn more about it. The last time we checked in with [soiboi], he was creating fluidic robots.