There are a variety of means by which numbers can be displayed from an electronic circuit, and probably the most ubiquitous remains the seven-segment display. Take seven LEDs, lamps, LCDs, VFD segments or mechanical flip-dot style units in the familiar rectangular figure eight, and your microcontroller or similar can display numbers. There are a variety of different interfaces, but at most all that is needed is a level shifter and a driver.
Sometimes though we encounter a completely novel 7-segment display, and such is the case with [Fhuable]’s all mechanical single digit display. It bears a superficial resemblance to a flipdot display, but instead of a magnetic actuator, it instead uses a complex system of gears and cams to flip the segments sequentially from the turning of a small crank. It appears to be the same mechanism he’s used in his subscription counter project whose video we’ve placed below the break, and it is truly a thing of beauty. We’re not entirely certain how useful it would be as a general-purpose display in its current form, however, we can see it being adapted with relative ease. A clock might, for example, be an eye-catching project.
Most displays that make it here have some electrical components, so it’s unusual to see an entirely mechanical one. But that’s not necessarily always the case.
Continue reading “Not All 7-Segment Displays Are Electronic”
[Irene Posch] is big into
knitted fabric circuits. And while most of the textile circuits that we’ve seen are content with simply conducting enough juice to light an LED, [Irene]’s sights are set on knittable crafted arithmetic logic units (ALUs). While we usually think of transistors as the fundamental building-blocks of logic circuits, [Irene] has developed what is essentially a knit crochet relay. Be sure to watch the video after the break to see it in construction and in action.
The basic construction is a coil of conductive thread that forms an electromagnet, and a magnetic bead suspended on an axle so that it can turn in response to the field. To create a relay, a flap of knit conductive thread is attached to the bead, which serves as the pole for what’s essentially a fabric-based SPDT switch. If you’ve been following any of our relay-logic posts, you’ll know that once you’ve got a relay, the next step to a functioning computer is a lot of repetition.
How does [Irene] plan to display the results of a computation? On knit-and-bead flipdot displays, naturally. Combining the same electromagnet and bead arrangement with beads that are painted white on one side and black on the other yields a human-readable one-bit display. We have an unnatural affinity for flipdot displays, and making the whole thing out of fabric-store components definitely flips our bits.
Anyway, [Irene Posch] is a textile-tech artist who you should definitely be following if you have any interest in knittable computers. Have you seen anything else like this? Thanks [Melissa] for the awesome tip!
Continue reading “Knitting ALUs (and Flipdots)”