
QR Code in shopping cart handle - samweinberg
http://mathematica.stackexchange.com/questions/26268/qr-code-in-shopping-cart-handle#
======
TheBiv
This screams marketing and engineering not being able to clearly communicate
the problem statement. The problem statement was given to engineering as "How
do we get a QR code inside of this handle thing?", when I am guessing their
actual question was something like "How do we get the shopper to engage with
our digital marketing efforts?"

I for sure know there are times when marketing has a clear thing of what they
want, and you are not allowed to brainstorm the pro's and con's; but the con's
seem to far outweigh the pro's in this specific strategy.

You're telling me that the shopper would have to contort their phone an
unnaturally specific angle just to scan a QR code. Now the problem statement
is back to the marketing team of "How do I tell the shopper to contort their
phone at this angle?". I doubt that the marketing folks will like this being
back on their lap.

~~~
Untit1ed
I'm not sure if I missed something, but the top answer says:

 _The question is what happens here. The theory behind it is pretty easy and
the good thing is, it explains what you have to do from any (meaningful)
viewpoint. Let's use a simple cylinder graphic as example to explain what I
mean_

I'm pretty sure his example is at a contorted sideways angle because it
demonstrates that you can line it up from any angle. The OP in the question
could reasonably expect that the customer will be facing the handle from
directly behind it when they push the trolley, and adjust his maths
accordingly.

~~~
TheBiv
I do not know either. But lets assume that unknown you pointed at is true.
What I do know is that if I look at the end result from a lay persons
perspective, it will look "weird". Weird meaning it doesn't look like a normal
QR code.

This will result in the same thing I initially mentioned in that marketing
will have to communicate to the shopper that they can use this just like a
normal QR code, which is a communication problem, not a tech problem.

------
timdorr
Whilst impressive, there's a far less mathematical solution:
<http://i.imgur.com/3QuYufc.jpg>

~~~
carlosaguayo
Reminded me about the story of the pen and pencil in the moon.

www.scientificamerican.com/article.cfm?id=fact-or-fiction-nasa-spen

~~~
vecinu
People still believe this myth? Especially on HN?

<http://www.snopes.com/business/genius/spacepen.asp>

~~~
tikhonj
Think of it not as a myth but as an amusing allegory.

~~~
jbooth
Because it's not truth that matters, it's truthiness. I don't need facts I can
understand with my brain, I need facts that I can understand with my gut.

------
paul9290
Are people using QR codes frequently here in the states or elsewhere?

To me I see them everywhere, but curiously most phones don't have them built
into their camera apps (iPhone's camera doesn't have built in scanner) or have
some quick an easy way to scan QR codes.

Rather you have to download an app and then later find that app, then fidget a
bit too much to get the app to read the code.

Not the greatest user experience and I have found it frustrating!

What advances have been made and or are being made to make QR code scanning
quick and painless?

~~~
mrud
<http://picturesofpeoplescanningqrcodes.tumblr.com/> SCNR

But on a more serious note google now/the camera search in android has QR code
support integrated and you don't necessarily have to install additional
applications.

~~~
mwilcox
Unfortunately they removed Search with camera in a recent update, hopefully
they will add it back in.

------
esolyt
I posted this 4 hours ago: <https://news.ycombinator.com/item?id=5810228>

How come HN allowed a duplicate link?

~~~
m0th87
OP added a hash (#) after the URL to make it unique

~~~
sc68cal
I hate when people do that. I posted the story to MJ's report on lead in
gasoline being linked to crime rates.

<https://news.ycombinator.com/item?id=5008285>

Someone posted the "print" version and got 333 points for it a couple hours
later.

~~~
manojlds
You are worried that you didn't get the karma points. I am glad that I was
able to find this because someone reposted it, when the other was lost to
oblivion.

~~~
esolyt
Honestly, I don't care about karma at all. I was just curious when I saw the
duplicate post. But now that I learned something can be reposted by adding #
at the end of it, I think it needs to be fixed.

------
ck2
Um, I never look at the cart handle.

However the inside of the back of the cart is flat and in 100% visual range.

------
mxfh
this might be actually useful if glued on a bikeframe:
<http://joe.framba.ch/qr-code-on-a-cylinder>

~~~
zachrose
Entertaining the idea that QR codes should be deformable onto curvilinear
surfaces, couldn't this be done by the QR reader, so that it's more "readable"
to a person that it is a QR code?

~~~
mxfh
I think in case of the bike frame the distortion is minor. As I understand
it's only there as proof of ownership for the people who really need to know
on a hopefully unlikely occasion. So making it not too obvious might be a good
idea when it comes to bike theft.

The QR-Code is meant to be easy to decode, adding compensation for non-planar
surfaces might make it non-trivial to implement on embedded devices.

------
RodericDay
I would've used transparent plastic with a QR code in the center. (So like
`(|)` from the side).

Awesome discussion, though!

------
emillon
As other comments note, this is missing the point a lot. QR codes are useful
(or supposed to be) because they can be scanned from a different perspective.
This solution requires a particular viewing angle and cannot cope with
perspective shifting, making it useless in practice.

For this particular problem, attaching a QR code to a flat surface (if
possible), or using "old fashioned" 1D barcodes (they probably carry enough
information) is probably a better solution.

The general problem is designing a high density, 2D barcode system that can
cope with perspective shifting with a cylindrical topology ; now that would be
a neat mathematical trick!

------
gggggggg
The answers on that site are impressive from a helpful perspective.

sometimes the internet is full of cat gifs, and other times you get great
minds in a sharing mood. This is what hn used to be when I started reading it.

------
rileyt
The better question is why are they using QR codes??

------
rurounijones
That has to be one of the most in-depth and informative answers in the history
of StackerOverflow.

I wonder if there is a "best of" search you can do.

~~~
itafroma
There is a "greatest hits" list for each Stack Exchange site: just add
/questions/greatest-hits to the end of the domain. Examples:

<http://serverfault.com/questions/greatest-hits>

<http://stackoverflow.com/questions/greatest-hits>

<http://mathematica.stackexchange.com/questions/greatest-hits>

<http://programmers.stackexchange.com/questions/greatest-hits>

There's of course an "is:answer" search sorted by votes for each site as well:

[http://serverfault.com/search?tab=votes&q=is%3aanswer](http://serverfault.com/search?tab=votes&q=is%3aanswer)

[http://stackoverflow.com/search?tab=votes&q=is%3aanswer](http://stackoverflow.com/search?tab=votes&q=is%3aanswer)

[http://mathematica.stackexchange.com/search?tab=votes&q=...](http://mathematica.stackexchange.com/search?tab=votes&q=is%3aanswer)

[http://programmers.stackexchange.com/search?tab=votes&q=...](http://programmers.stackexchange.com/search?tab=votes&q=is%3aanswer)

~~~
rurounijones
Excellent, thank you very much.

------
lazugod
This was more interesting/informative than logos-in-CSS posts, and yet many of
the comments are negative.

~~~
manojlds
Many of the comments on that one were negative too. What is interesting for
one person is dumb for another anyway. For me, both the css-logos, and this QR
code on a cylinder were nice to see from a theoretical point of view, but I
don't see any practical use.

------
utopkara
How hard is it to put a flat surface on the shopping cart? Why is the cart
handle the best place to put the QR code? I am pretty sure the method will
come in handy, and the way the solution is presented is awesome though.

~~~
sopooneo
It seems likely to me that the marketing people are working with a third party
to do that actual construction and installation of the adverts. Their options
for what physical shaped plastic the advert will go in are certainly limited
and there may be no option for flat plastic, or the marketers may not realize
the utility of such an option. But I would be very surprised if the marketers
could specify a custom shape for the plastic.

------
downandout
Why not print the QR code on a sticker, and place the sticker on the plastic
flap on the cart?

~~~
ryanklee
Because that's where little Jimmy/Susie and/or a pile of bananas is currently
sitting.

