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Open source “split-flap” mechanical display

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Re: Open source “split-flap” mechanical display

#31

Post by argvargc »

danohuiginn wrote: post #29
argvargc wrote: post #23

Genuine question: what are some practical advantages of a split-flap display over, well... any other kind of dynamic character display? The only two I could think of are: - they don't emit light, so maybe there could be some kind of light-sensitive situation where this would be required (though in that case e-ink would surely surpass it). - the sound passively-alerting those present to updates. It's not obtrusive or…

Nostalgia, really -- I have fond associations of these with childhood train journeys. I could just about imagine a genuine use case in some kind of hostile environment. You could probably make one of these very resistant to water/temperature/radiation, with the controller kept safely out of the way.

That sparked an interesting idea: would these work in a zero-gravity situation (mechanically I mean), and if not, how to adapt them so they would?

(And agree with the nostalgia - I'm sure for many the sound is associated with a quiet anticipation or excitement of embarking on a journey.)

Re: Open source “split-flap” mechanical display

#32

Post by gattilorenz »

argvargc wrote: post #23

Genuine question: what are some practical advantages of a split-flap display over, well... any other kind of dynamic character display? The only two I could think of are: - they don't emit light, so maybe there could be some kind of light-sensitive situation where this would be required (though in that case e-ink would surely surpass it). - the sound passively-alerting those present to updates. It's not obtrusive or…

similarly to an e-ink display, it doesn't take energy to show the current/last status, it's required only for transitions. If there's a blackout, the display is still visible.

Re: Open source “split-flap” mechanical display

#33

Post by CyanDeparture »

argvargc wrote: post #23

Genuine question: what are some practical advantages of a split-flap display over, well... any other kind of dynamic character display? The only two I could think of are: - they don't emit light, so maybe there could be some kind of light-sensitive situation where this would be required (though in that case e-ink would surely surpass it). - the sound passively-alerting those present to updates. It's not obtrusive or…

To me it's as simple as they look really cool and satisfying.

Re: Open source “split-flap” mechanical display

#34

Post by smnscu »

gibolt wrote: post #4

Related video on Flip Clocks from Technology Connections: https://youtu.be/ZArBfxaPzD8

I really enjoy Alec's videos and quirky humour. Beware though, this kind of channel is a massive, addicting time sink. Other similar channels that HN might appreciate (the first two are quite well-known, the last one I found recently and is definitely bingeworthy):

- Smarter Every Day https://www.youtube.com/channel/UC6107grRI4m0o2-emgoDnAA

- Tom Scott https://www.youtube.com/user/enyay

- Practical Engineering https://www.youtube.com/user/gradyhillhouse

Re: Open source “split-flap” mechanical display

#35

Post by TonyTrapp »

smnscu wrote: post #34
gibolt wrote: post #4

Related video on Flip Clocks from Technology Connections: https://youtu.be/ZArBfxaPzD8

I really enjoy Alec's videos and quirky humour. Beware though, this kind of channel is a massive, addicting time sink. Other similar channels that HN might appreciate (the first two are quite well-known, the last one I found recently and is definitely bingeworthy): - Smarter Every Day https://www.youtube.com/channel/UC6107grRI4m0o2-emgoDnAA - Tom Scott https://www.youtube.com/user/enyay - Practical Engineering https:…

> Beware though, this kind of channel is a massive, addicting time sink

Luckily he only posts new videos every few weeks. ;) And almost every one of them is time well spent.

Re: Open source “split-flap” mechanical display

#36

Post by pault »

huhtenberg wrote: post #21

> laser cut enclosure Had a quick look and the cheapest laser cutter appears to be around $400. The next one is $1500 and then the price just keeps on climbing. Any first-hand experiences with laser cutters? An option suitable for an (occasional) hobbyist use, but not a total junk either.

You can send your designs to ponoko for small batches. Much cheaper than buying a laser cutter unless you plan to scale up.

Re: Open source “split-flap” mechanical display

#37

Post by mjhagen »

danohuiginn wrote: post #29
argvargc wrote: post #23

Genuine question: what are some practical advantages of a split-flap display over, well... any other kind of dynamic character display? The only two I could think of are: - they don't emit light, so maybe there could be some kind of light-sensitive situation where this would be required (though in that case e-ink would surely surpass it). - the sound passively-alerting those present to updates. It's not obtrusive or…

Nostalgia, really -- I have fond associations of these with childhood train journeys. I could just about imagine a genuine use case in some kind of hostile environment. You could probably make one of these very resistant to water/temperature/radiation, with the controller kept safely out of the way.

I used to have one of these, but left it above the radiator. All flaps warped beyond repair :( So if you're going for resistance to harsh environments you'd have to source a better material for the flaps, at least.

Re: Open source “split-flap” mechanical display

#38

Post by abetusk »

murderfs wrote: post #22
abetusk wrote: post #19

Scott Bezek has a great video on "How a Split Flap Display Works" [0]. He also sells blank "flaps" on Tindie [1]. The documentation on how to build the Split Flap is also really awesome [2], including how to cut your own flaps [3]. I've been following this project for a while. It's pretty awesome. I estimate about $10 per character (as opposed to the $180/character (!!) another poster mentioned through Alibaba), with…

> I've been following this project for a while. It's pretty awesome. I estimate about $10 per character (as opposed to the $180/character (!!) another poster mentioned through Alibaba), with a large portion of the cost being the custom cut "flaps" (in small quantities). It seems like the cost could get in the $2-$4 range per character but I couldn't figure out how to do it without a significant amount of labor involv…

Laser cutting is straight out for the hobbyist, because of the chlorine, as you correctly point out. I think the way to do this is either with a CNC or with some die punch solution.

Doing a single cutout of PVC with a CNC would be fine, but doing 40x23x7 is probably not.

Doing a die punch is maybe possible but I don't really know how to create a custom punch and what tooling to use.

Re: Open source “split-flap” mechanical display

#39

Post by martin_a »

argvargc wrote: post #31
danohuiginn wrote: post #29

Earlier quoted context omitted.

Nostalgia, really -- I have fond associations of these with childhood train journeys. I could just about imagine a genuine use case in some kind of hostile environment. You could probably make one of these very resistant to water/temperature/radiation, with the controller kept safely out of the way.

That sparked an interesting idea: would these work in a zero-gravity situation (mechanically I mean), and if not, how to adapt them so they would? (And agree with the nostalgia - I'm sure for many the sound is associated with a quiet anticipation or excitement of embarking on a journey.)

They probably won't.

After a flap has passed the upper lip, which is kind of holding it back to have a precise "flipping point", gravity will take care of moving it down.

No gravity, no flap. ;-)

Re: Open source “split-flap” mechanical display

#40

Post by mschuster91 »

argvargc wrote: post #23

Genuine question: what are some practical advantages of a split-flap display over, well... any other kind of dynamic character display? The only two I could think of are: - they don't emit light, so maybe there could be some kind of light-sensitive situation where this would be required (though in that case e-ink would surely surpass it). - the sound passively-alerting those present to updates. It's not obtrusive or…

- they don't require energy to maintain their state - a property which they share with eInk displays, but a split-flap display is unrestricted in size.

- assuming a fixed output selection, a split-flap display can also achieve far greater visual quality than other competitors like flip-dot displays

- defective units can be automatically detected (by comparing the position of the indicator magnet), whereas stuck pixels in flip-dot, matrix or LC displays require a human to spot them

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