F21 Thread Screen

Beautiful piece. I was also a big fan of the dot display you guys did previously...

https://www.youtube.com/watch?v=x3jkoIyJgoc

Seriously, if you ever thought about mass-producing the dot module (or even a split-flap character display), I'd buy them by the hundreds.

Great video - hope to see a longer one / blog post if F21 lets you publish details.

Is there a story behind the PCB that's shown on fire, or was that just for show? ;)

I had a hunch this was a BREAKFAST piece before I even clicked the video. Really impressive project. Love what you guys have been doing!

Would you have any interest in demoing this at the "other" breakfast in NYC - NYC TechBreakfast? Check it out at http://meetup.com/nyc-techbreakfast and drop me a line if so.

Given the popularity of this on HN, you should consider adding a link to your jobs site.

How long did this take to make? Very cool project!

While I understand the point you are making, I would argue that the textile industry is a necessary evil for many countries. It's pretty well explained in this article:

>According to the comprehensive “Ashgate Companion to the History of Textile Workers,” a study of 21 countries over 350 years, nearly every nation suffered through its T-shirt phase differently. Argentina’s brutal encomienda system literally worked indigenous laborers to death. The Hapsburg monarchy’s T-shirt phase coincided with its own collapse. Japan’s progress was slowed by a world war; Germany’s was all but destroyed by two. New England’s textile workers had it relatively good; if conditions didn’t improve, they could threaten to leave for the frontier.

>All these countries, however, experienced the same broad phenomenon. Lex Heerma van Voss, an editor of the “Ashgate Companion,” told me that the T-shirt phase lasts only as long as there are large populations of farmers with few options. This is known as a “race to the bottom.” Factory owners compete by offering low prices, which are accomplished by paying workers tiny wages. Cutting costs by a few pennies per shirt may sound trivial, but mass-market brands find that even a slight increase in price destroys demand. And those pennies at wholesale become dollars at retail.

>But once the factories have absorbed all these desperate farmers, they need to find a new competitive advantage. That usually involves making better products. When the T-shirt phase ends, a “race to the top” usually begins. Factories often shift to finer clothes, like dress shirts, which require skilled workers. This phase often involves the growth of unions and rising wages. It’s typically followed by one in which factory owners, forced to pay more, seek out ever more profitable lines of business. That can mean the move to low-end electronics assembly, then auto plants and maybe even airplane manufacturing. At the high end of the spectrum, you begin to see what the U.S. manufacturing economy is going through now — expensive products, like medical devices, which are often made by machines that are operated by highly skilled workers.

http://www.nytimes.com/2013/05/19/magazine/economic-recovery...

As long as there is no slave work, this is, people are working in these factories "voluntarily", it may be the best option they have. These are people maximizing their utility and deciding to work for USD50-200/month with 6 day weeks and 12 hour days. Yes, it sucks, and I wish they had other options, but I'm not sure that boycotting F21 would work in their favor. As the article sadly states, this seems like a necessary phase.

Re the self-correction, perhaps it's this:

> Each ribbon also features a reflective strip which is scanned by an infrared sensor, which tells the machine the color each spool is currently showing, allowing for corrections for any slip that may occur.

Source: http://breakfastny.com/f21-thread-screen-press-release

Given the project's scope and budget for the agency I guess doing this with actual threads would have made it very hard to maintain on site, magnitudes slower and result in a skyrocketing part count. So this compromise is fair and still impressive.

BREAKFAST did a display before which might have been even more impressive: http://breakfastny.com/dot-screen

I too found it quite confusing, I kept trying to figure out where the threads were, was it stitching fabric real time?

Quite disappointed when I saw it was just colored bands spinning. I might have thought it was cool if I had gone in expecting bands, but expecting actual thread, and seeing bands was a let down.

If you look closely, the bands are covered in (multi-coloured) threads.

It would have been nice with some kind of closed loop feedback system for all positions around the ribbons, but it became a cost problem. What we did instead was to put an IR sensor on the motor controller behind each motor. The fabric ribbons are fitted with a retroreflective strip for homing. This gives us one absolute starting point on each pixel and then each color is just at a fixed ustep offset from zero. But as you pointed out, some of the ribbons are slipping a little bit so they are a color our two out of cal. The ribbons are real fabric ribbons, not timing belts so that's why we do have some slip. We periodically run the strip over the IR sensor to zero out the calibration so bad pixels should re-align at least a little bit over time. If they are really bad, we take them down and swap in a spare 32 pixel module while tightening the belt on the bad ones.

And ideally not just using an encoder to detect skipped steps or something. But using some kind of vision to close the loop using color since you're making an image.

At the very least put a Gray code on the back of every fabric loop to get actually accurate positioning.

just the one.

Well they actually built something unlike running an ad would do.

And I think you're lowballing the number of colors. Not that it needs a huge amount.

I agree, but I don't think it'll happen until their consumers demand it.

How can it be a knockoff? It's not like he was the first ever to do it. His non-LCD projects aren't in color. This is much bigger than any of those.

Knockoff feels a bit harsh. Inspired, perhaps?

that's a serious stretch