
Sprayprinter – A graffiti robot startup - SiftedTech
https://sifted.eu/articles/the-graffiti-robot-startup-thats-turned-down-millions/
======
Vaskerville
This seems like a good moment to remind about Jürg Lehni & Uli Franke's Hektor
(2002):
[http://juerglehni.com/works/hektor](http://juerglehni.com/works/hektor).

~~~
sf_rob
This one is so much cooler. Linear controlling is the obvious solution, but
this does the proper approach angles which is awesome.

------
sweetheart
I can’t help but feel that in some ways, an “artistic” ad is even worse than
one that doesn’t try to appeal so strongly to aestheticism for the sake of
beauty. It’s somehow more deceptive and insidious to me. I don’t think the
founders adhere to much of an ethical code if they are commissioned for any
ads.

~~~
cwkoss
Elevating advertising with art cheapens the art. Mona lisa would be ugly
garbage its intention was to sell insurance.

~~~
gumby
_La Jaconde_ /Mona Lisa it was funded to promote the glory of François 1er.

------
smoyer
If you're into robots watch one of the FirstInspires events on Twitch. Sitting
in the stands at the Greater Pittsburgh Regional ATM ... It's pretty amazing
what high school students can build!

~~~
SiftedTech
Is this the right link?
[https://www.twitch.tv/firstinspires/events?filter=past](https://www.twitch.tv/firstinspires/events?filter=past)

~~~
pietroglyph
I don’t think that will get you a competition livestream. Most competitions
this week haven’t started yet (they’re usually ~Fri-Sun). The game changes
every year, but here’s a sample match from last year:
[https://youtu.be/jYjztOCT79M](https://youtu.be/jYjztOCT79M)

You might also be able to find something at a week 4 event today or tomorrow
here:
[https://www.thebluealliance.com/#events](https://www.thebluealliance.com/#events)

The _FIRST_ Robotics Competition is really cool (it turned 30 yesterday!), and
if you like the look of it you should consider checking out or even mentoring
a nearby team. They exist in many US high schools, and in some other countries
as well.

~~~
smoyer
It will get you a live stream of the practices I our region ...equals are all
day Friday and Saturday morning and the finals are Saturday afternoon (about
half an hour from now).

------
tokyodude
The definition of graffiti pretty much includes property destruction. I don't
get why that's ok with so much of Western culture.

I think street art is great and with permission have zero issues but going
around trashing other people's property seems like a net negative to society
as a whole. It sets a precedent. If you can trash my stuff then it should be
okay for me to trash yours. That seems like a bad direction to me.

~~~
laughinghan
Is it your understanding that non-Western cultures would be more or less okay
with graffiti? Seems like everyone else is if anything _less_ absolutist about
private property rights.

I'm sorry you think that what I did to your stuff trashed it, but I think I
enhanced it/everyone else thinks I enhanced/I didn't think you cared? It's on
your outside wall, everyone else in the world has to stare at it/pass by it
too, whereas from inside you can't even see it.

Sure, strictly speaking, legally no one has any right to do anything to it but
you. But like, if you're asking why societally, culturally, it's socially
acceptable to do stuff to that wall, I don't understand why that's hard to
understand? No harm no foul; like, if I _set fire_ to your building, no one
thinks that's harmless or acceptable. But if I paint something on your ugly
outside wall, why would anyone be up in arms about that on your behalf?

~~~
tokyodude
then maybe you should grafitti the Sistine Chapel. You claim you're making it
prettier but why is that up to you? If want to paint it make a proposal and
ask for permission.

Besides beauty is in the eye of the beholder. 95% of the graffiti I see is
just someone's name/callsign/initials. It's not remotely pretty. It's just
blatent selfish self promotion

~~~
laughinghan
> then maybe you should grafitti the Sistine Chapel. You claim you're making
> it prettier but why is that up to you?

Of course it's not up to me? You asked how it could be "ok with so much of
Western culture". If we _collectively_ think it's prettier, like those Banksy
pieces that were going to be removed but were instead made permanent due to
public outcry, then we're okay with it. If we collectively think it's
dumb/ugly/meaningless, like tagging (which is what it's called when people
just write their name or initials or gang sign or sports team is apparently
really common, too), then no one minds if we remove it, and there's certainly
not much respect for it. If someone destroyed priceless cultural heritage like
the Sistine Chapel by spray-painting over it, do you really believe that would
be "ok with much of Western culture"?

------
nerpderp82
This is a wire robot but operating in a plane (or curved plane on the side of
the water tower).

[https://www.researchgate.net/figure/A-spatial-wire-robot-
a-C...](https://www.researchgate.net/figure/A-spatial-wire-robot-a-CAD-Draft-
of-WiRo-b-Geometry-and-kinematics_fig1_200556782)

I would use a single pivot at the top and two wheels in contact with the
plane, the path of the robot would then be an arc around that pivot point. The
rest of the mechanism is analogous to an ink-jet printer.

The other option would be to construct a large
[https://reprap.org/wiki/CoreXY](https://reprap.org/wiki/CoreXY) like
mechanism, forming a large etch-a-sketch. I have also seen devices that used
venturi suction to drive on vertical surfaces. Or suction cups mounted on
pivoting arms that could walk across the surface.

~~~
SiftedTech
Thank you for these insights.

------
michaelbuckbee
Have you seen Maslow? An open source large format CNC machines? It may have
some ideas that you could apply:

[https://www.youtube.com/watch?v=y60q6U7NjTQ](https://www.youtube.com/watch?v=y60q6U7NjTQ)

------
MayeulC
I thought a lot about a similar concept, using drones (maybe even swarms). Has
this ever been attempted? I guess the energy and posioning constraints would
be much tighter, but it would make for a fun project.

One advantage I see to using strings and wheels is that there is no strict
requirement for spray painting, as it can be done with regular rolls. I was a
bit disappointed to see that it used spray painting here as well (and quite a
bit of sprays bottles per painting).

------
utexaspunk
I would imagine it's stepper motors and rotary encoders turning the pulleys,
with perhaps some solenoids or servos to push the tops of the cans.

~~~
ninju
Along with some kind of Z-axis calibration to validate height (GPS or
barometer based) since drift due to slippage or weight changes is quite
possible

~~~
haihaibye
Or markers on the wires.

------
pedro1976
Some time ago I was brain storming about something similar but with a
different tech stack to be able to plot from the distance. I wanted to mount a
spray can on a quad-copter and keep the power supply external initially. The
ultimate goal was to mark an area of wall using a separate device (mobile
phone maybe) and the quad-copter would then fly there and do its work.

~~~
sleepybrett
Check out GRL's old `l.a.s.e.r. tag` project. Projector based but used machine
vision to draw on top of a laser pointer mark.

[https://github.com/LeonFedotov/L.A.S.E.R.-TAG-
GRL](https://github.com/LeonFedotov/L.A.S.E.R.-TAG-GRL)

------
mark-r
It's just an ink jet printer, scaled really large. The print head moves via
motors and pulleys in steps along two dimensions. Unless there are patents
that specifically apply I think just about anybody could do it.

Their dedication to art vs. advertising seems doomed to failure once somebody
replicates the device.

~~~
coldtea
> _It 's just an ink jet printer, scaled really large._

Yeah, just like Dropbox is basically an FTP account, mounted locally with
curlftpfs, and then SVN or CVS on the mounted filesystem. Not to mention that
from Windows or Mac, this FTP account could be accessed through built-in
software.

~~~
mark-r
Before the post title was changed it contained a question, "any idea how its
hardware works?" That's where my comment was directed.

~~~
SiftedTech
I haven't changed my question - don't know why it's been edited or how?

~~~
yorwba
The guidelines admonish us to "...please use the original title, unless it is
misleading or linkbait; don't editorialize."
[https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)

------
sleepybrett
there are several versions of this basic robotic design available for purchase
both diyish and fully fledged products (neither one I'm about to list is spray
paint based though, but in the case of the diy version, it could be hacked in
with a redesign of the 'shuttle')

Sandy Noble's Polargraph (diy and very hackable) :
[http://www.polargraph.co.uk/](http://www.polargraph.co.uk/)

the Scribit (buttoned up product with multiple pen support) :
[https://scribit.design/](https://scribit.design/)

This looks like the exact same system but because of the pendulum effect when
you "turn a corner" these guys wen't with just running it up and down in
vertical lines and only moving a bit to the side when the line is done.

------
haihaibye
Cool. Now please cover lots of ugly concrete walls with L-System fractals!

------
joshvm
You can see the cabling in the video on the official site:
[https://www.sprayprinter.com/](https://www.sprayprinter.com/)

------
perch56
Interesting as I just watched last night on Netflix, “Love, Death & Robots
Episode 14: Zima Blue” which is a story very similar to the robot from the
article.

------
sparrish
Looks like it crawls up and down wires

------
bryanrasmussen
consider Grafitti Markup Language
[http://www.graffitimarkuplanguage.com/](http://www.graffitimarkuplanguage.com/)

------
shaunxcode
The technical aspect is cool for sure but I think the more important point is
the anti-advert/commercial art stance being taken. It is extremely refreshing
and inspiring.

~~~
hinkley
Except they took the Nissan commission. The aren't anti-commercial, they're
just commercial averse. Like Google is evil averse. If you're neutral you get
to do bad things without being bad.

A lot of people want to be good as long as they don't have to sacrifice
anything for it. Really, as long as they don't see themselves as actively
engaging in the other direction, they sleep really well at night. They aren't
good, they're just normal, but it's enough to maintain the illusion of their
self image as a good person. If I'm not an asshole then I must be a good
person.

Which I think is why we have so much trouble changing our peers. The moment we
bring something up we've already challenged their identity. We've issued an
existential threat. We might as well be brandishing a knife.

From the other side, when I give up things for philosophical reasons, some
people characterize this as self-destructive behavior. A sign of naivete. Of
immaturity. I only know two things. They probably sleep better than I do, and
I'll sleep even worse if I don't do these things.

I begin to wonder if it's the case that the only people who _are_ good people
will tell you that they aren't. Kind of depressing if true. Think of your
favorite person and imagine that you like them better than they like
themselves. Harsh.

~~~
SiftedTech
Being averse is still a good start though? - I was just wondering how long it
would take for someone to replicate the technique and sell out...

~~~
hinkley
In any other industry.

Maybe I'm getting sucked in by stereotypes but it seems like the art community
is much more concerned with 'selling out' than most.

On the other hand, a plot device from a scifi book (Tad Williams I think?) has
stuck me with the idea of creating slowly evolving graphics. If I were an
artist I might get pretty excited about a robot who can paint and repaint a
mural for me as many times as I want. Being able to change with the seasons or
local events might entice me, regardless of how many ads have done the same
thing.

------
duado
These guys aren’t anti-advertising as much as they are protecting their
bohemian “too cool for capitalism” brand.

------
fenwick67
Graffiti !== Spraypaint

------
emilfihlman
Raster lines, nothing special.

~~~
igor47
Do you remember when you became bitter and jaded?

~~~
crossman
When I clicked this the title was asking how this was working. I think that's
what this user was answering

~~~
SiftedTech
Hi yes this is what I was asking. I don't know why the title has changed!

~~~
dang
Moderators change titles when they break the site guidelines. The relevant
guideline is " _Please use the original title, unless it is misleading or
linkbait; don 't editorialize._"

[https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)

The submitted title was "Wall-climber robot spraypaints big murals, any idea
how its hardware works?", which is actually more baity than the original
(wrong direction!). It's also the sort of thing that will strike HN readers as
transparently promotional, prompting them to flag a submission.

