
Show HN: Chalkbot - tunavargi
http://engineering.hipolabs.com/chalkbot/
======
kator
I built a dual axis laser pointer setup to play with my cat but she looks at
the servo's too often because they're so noisy. I was wondering if I could use
memory wire to control the laser pointer since it would be quieter.

Now I'm wondering if these stepper motors might be a better alternative, maybe
a third one against some sort of a spring loaded harness.

Either way very cool, would be interesting to see if a third motor might have
helped rather than relying on gravity and good behavior of the chalk pen.

------
em_
I am doing similar drawings with Sandy Noble's Polargraph
([http://www.polargraph.co.uk](http://www.polargraph.co.uk)). How do you keep
the liquid chalk flowing? Common liquid chalk pens need pumping over time.

art+com created a massive chalkbot at Jelling Museum in Denkmark:
[https://artcom.de/en/project/experience-centre-royal-
jelling...](https://artcom.de/en/project/experience-centre-royal-jelling-2/)

------
Qworg
And here I thought it was the Nike Chalkbot:
[http://m.youtube.com/watch?v=HmW-eGCrSxs](http://m.youtube.com/watch?v=HmW-
eGCrSxs)

Still cool though!

~~~
colindean
Nike Chalkbot was a project by Pittsburgh-based Deeplocal:
[http://www.deeplocal.com/projects/chalkbot.html](http://www.deeplocal.com/projects/chalkbot.html)

~~~
goodmachine
Historical note on the evolution of drawbots: Nike's Chalkbot was a direct and
uncredited steal of IAA's Graffiti Writer robot project/ Streetwriter truck:
from political dissent to branded drivel in one smooth move.

The OP's Chalkbot however announces itself as being inspired by Jurg Lehni's
HEKTOR (2002). Scholars (HT @Sandy Noble of Polargraph) will note HEKTOR's
twin-cord design from 2.30m in this deeply awesome MIT MediaLab/ SIGGRAPH
video from 1988. Made of Lego! Programmed in LOGO!

Presume there are antecedents (pendulographs, anyone?) for this too. AFAICS,
Lehni does not acknowledge the MIT crew anywhere... tsk tsk.

ACM SIGGRAPH 1988 Issue 40 - Lego/Logo

[https://open-video.org/details.php?videoid=8213](https://open-
video.org/details.php?videoid=8213)

Graffitiwriter vs Nike Chalkbot

[https://vimeo.com/6075609](https://vimeo.com/6075609)

[http://blog.nearfuturelaboratory.com/2009/07/07/chalkbot-
ver...](http://blog.nearfuturelaboratory.com/2009/07/07/chalkbot-versus-
graffitiwriter/)

Polargraph

[http://polargraph.co.uk](http://polargraph.co.uk)

Nice resource for drawing machines here:

[https://drawingmachines.org/index.php](https://drawingmachines.org/index.php)

------
chris_st
That's great! Thanks for detailing what went wrong, as well as what went
right.

I've wanted to do a drawbot (paper and pen) for a while, and thought these
pulleys[1] and belts[2] might be good.

1:
[https://www.adafruit.com/products/1251](https://www.adafruit.com/products/1251)
2:
[https://www.adafruit.com/products/1184](https://www.adafruit.com/products/1184)

------
rosalinekarr
I wonder what this would look like if they could speed up the motors and
smooth out the motion with some more taught string. Maybe they could recreate
more hand-like motions.

~~~
mangodrunk
If you're in San Francisco, at The Interval, they have a chalkboard drawing
robot similar to Chalkbot: [http://blog.longnow.org/02014/03/13/interval-
chalk-board-rob...](http://blog.longnow.org/02014/03/13/interval-chalk-board-
robot/) Also,
[https://www.youtube.com/watch?v=GpQzIaH90f8](https://www.youtube.com/watch?v=GpQzIaH90f8)

These projects are really cool.

~~~
GoodOldNe
There is also a very cool chalk drawing robot installed at the SF MOMA.

------
StavrosK
Very nice! I made a similar ones with LEGO Mindstorms in three dimensions:

[https://youtube.com/watch?v=blYpo2qB_LI](https://youtube.com/watch?v=blYpo2qB_LI)

