Making a Custom QR code plaque

[DaveC426913]

TL;DR

Experimenting with making my own QR code to connect to my WIFI

Got to say, I am pretty disappointed.

I've seen QR code plaques in people's houses. A guest scans it with their phone and it automatically connects them to the house Wifi.

Here's one made out of LEGO - I found on Google (It goes to something called Quasar.)

LEGO has been done, so I wanted to make something that befits a nice living room. I had planned to make one out of seed beads.

This is my mocked up Photoshopped prototype to test the colurs and contrast (obscured so I don't reveal my network creds to the world):

I assumed that camera s/w is smart enough to detect a QR code in widely adverse conditions, but my experiments are revealing that that is not the case. It could not read the above image. (It is quite new. Samsung A14 w/ Android)

So I backtracked to see just how precise the pattern needs to be for my phone to recognize it.

Here is the same pattern in black and white:

No joy. My camera did not recognize it.

The only difference between this and the generates one is that mine uses round dots - which are allowed, by the way - but apparently they can't have any gap between them.

Even this is too much whitespace:

My phone won't register this as a QR code until the black dots are touching each other:

Which kind of puts the kibosh on the whole project. There's just no way to create a real-world QR code plaque out of objects that has zero gap between them. Besides, even if it could be done, it would kind of defeat the purpose, since they wouldn't be distinguishable to the eye either - ruining the whole effect.

I am defeated.

 

[DaveC426913]

I also made a much faster experimental prototype by painting the dots on a piece of glass, which - if it had worked - would have been very elegant (though a bit inconvenient to use, since you have to get the lighting just right and avoid any shadows).

Anyway, it didn't work.

 

[DaveC426913]

In a totally unrelated story:

For sale:
- selection of seed beads in several colours and sizes, bottles of acrylic paint, small, square picture frames
Value: ~$75

$75 off if you come and pick them up.

 

[jedishrfu]

What about square black and white mosaic tiles like those used in bathroom remodels?

You might find something better in an arts and crafts store for doing mosaic designs.

You could glue them to a board or use double stick tape.

 

[DaveC426913]

What about square black and white mosaic tiles like those used in bathroom remodels?

You might find something better in an arts and crafts store for doing mosaic designs.

You could glue them to a board or use double stick tape.

LEGO has a resolution of 8.5mm (1/3 inch) per pixel. Which makes a LEGO QR code a whopping 11 inches on a side.

I wanted something more elegant. Less than 5 inches, ideally.

And I want it to be pretty, which is why I was going with glass seed beads, which can have have a beautiful effect. Also, I could weave them on invisible thread inside a frame that has no front or back - a little like a dreamcatcher, without all the feathers and hangy bits.

 

[Baluncore]

LEGO has a resolution of 8.5mm (1/3 inch) per pixel.

Is LEGO really based on one barleycorn = 1/3 inch = 8.467 mm ?

 

[Baluncore]

100 years ago, the barleycorn, (1/3 inch), was the UK standard for square ruled paper, and measuring shoe sizes. The barleycorn was not used on the European continent.

Alan Turing went to Paris in January 1940, to meet with the French and Polish cryptanalysts, because he couldn't follow the Polish instructions on how to read Enigma. Once the Poles had explained Enigma, they went on to ask Turing why the UK squared paper was ruled on an irrational 8.5 mm grid, which Turing then explained as the barleycorn.

The references I see show that LEGO is based on a metric stud pitch of 8.000 mm. The outer walls of blocks, are then pulled back, to have a clearance of 0.10 mm, ±0.01 mm.
So a 2 x 4 stud LEGO block measures, on average:
(2*8)-0.2 = 15.8 mm, by (4*8)-0.2 = 31.8 mm.

 

[robphy]

LEGO has a resolution of 8.5mm (1/3 inch) per pixel. Which makes a LEGO QR code a whopping 11 inches on a side.

I wanted something more elegant. Less than 5 inches, ideally.

https://en.wikipedia.org/wiki/Nanoblock#Design

Nanoblocks are similar in design to a Lego brick but smaller, with the smallest brick being 4 mm × 4 mm × 3 mm, not including the stud.

https://www.kawada-toys.com/brand/nanoblock/

https://nanoblockus.com/nanoblocks-vs-lego/