We’ve gotten used to seeing “meta clocks,” clocks that use an array of analog clock faces and piece together characters using the hands of the clocks. They’re very clever, and we always like to see them, especially when they come with detailed build instructions like this one does.
What’s also nice about [Erich Styger]’s “MetaClockClock” display is the twist on the original concept. Where most clock-of-clocks depend on the contrast between the hands and the faces of the analog movements, [Erich] added light to the mix. Hidden inside the bezel of each clock is a strip of RGB LEDs; coupled with the clear acrylic hands of the clock, which act as light pipes, each clock can contribute different shapes of different colors to the display. Each clock is built around a dual-shaft stepper motor of the kind used in car dashboard gauges; the motors each live on a custom PCB, while the LEDs are mounted on a ring-shaped PCB of their own. Twenty-four of the clocks are mounted in a very nice walnut panel, which works really well with the light-pipe hands. The video below shows just some of the display possibilities.
[Erich] has documented his build process in extreme detail, and has all the design files up on GitHub. We won’t say that recreating his build will be easy — there are a lot of skills needed here, from electronics to woodworking — but at least all the information is there. We think this is a beautiful upgrade to [Erich]’s earlier version, and we’d love to see more of these built.
So… ??HOW?? did they form that “8” (particularly the middle sides with the 3 arms)?
I was going to say “It just takes a second (hand).” But I see that for that example, he make one of the hands double-length (for the central clocks only). It’s the LEDs that decide whether a double-length hand is really double-length or not.
Yes, it is the LED (or better: the firmware) which decides if the hand is shown or not. Each hand on a ‘clock unit’ can be configured as ‘normal’ or ‘extended’ hand, and if and how the hand (or part of it) shall be ‘on’ or ‘off’. I feel it is more of a personal taste if using extended hands or not: writing text and digits works better with one extended hands in the middle row. For various animation patterns I feel a ‘normal’ hand setup works better. Changing hands and apply firmware configuration is a matter of minutes anyway :-)
24h clock FTW!
86400s clock rules them all!
23 h 56 min 4s clock… I’m on sidereal time… the one true time.
Yes, showing the seconds would be nice. It can show one more digit for seconds (10 of seconds) if running it in 12h mode, but it is not ideal so I dropped that idea.
I have a 60 unit version using the same hardware here: https://mcuoneclipse.com/2020/12/26/new-metaclockclock-v3-finished-with-60-clocks/
This one has more space to ‘write’ text and digits (there are different ‘fonts’ implemented with 2×3 the smallest one. What I doing on that 60 version and on the previous versions (V3: https://mcuoneclipse.com/2020/05/24/60-billion-lights-2400-rgb-leds-and-120-stepper-motors-hiding-behind-canvas-art/) is showing the seconds with the LED rings as it has 60 of them.
Same approach works on the 24 version too (using the LED rings to indicate the seconds).
While this appears to be a clock made of clocks,
in reality, it appears to not be made of actual clocks.
At least, not typical clocks.
That’s because in a typical analog clock the minute and hour pointers are not independent but always move together in a 1:12 ratio.
Which gives me an idea:
It would be cool to make a clock from an array of “actual” clocks:
Buy 24 identical, cheap, analog quartz clocks,
open their mechanisms, disconnect the coil (of the motor) from the quartz oscillator and connect to a microcontroller instead.
Then to drive the clocks, just send the correct number of impulses to the motors to achieve the required position.
Of course, it’s not possible to achieve an arbitrary angle, for example not possible to have ideally 90 degrees with one vertical pointer and one horizontal, but it’s possible to get close enough.
It could be worth trying.