Vertical Painting device

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I've been working for a while on this project but now I've reached something close to a 0.1 version. I just suck at mechanical devices design. The system is copy of a similar project done at Cornell University and at école cantonale d'art de Lausanne but it happened to be more of a challenge that I assessed initially. Now that it is up and running I am using it to ease the process of transfering drawings to a canvas. I still have to discover why I am getting a 12% compression on the y-axis but in the mean time I can easily compensate for that.

I wanted to use a solenoid for the pen up and down control but I did not manage to get a reliable behavior so I am using a third stepper motor I ripped off from a floppy drive (I use two stepper motors for controlling the two hanging strings). I am using coal sticks to draw over the canvas and I've noticed that next version will need to include a compensation of the wear of the coal (as it gets shorter as lines are being drawn) to avoid the system to stop drawing when only half work is done.

My project is entirely controlled by a PC using Visual Basic code.

Update: For those of you so lazy that cannot click thru read on the slides below to get a more detailed explanation of what this thing is about:

Comments

_Pablo_ said…
jey,llu, teik a luk at dis:

http://personales.ya.com/perropinto/robotidus/2006/09/pruebas-de-precision-e-intensidad.html
http://robotidus.mypets.ws/

Pablo
6:11 pm
misan said…
Cool Pablo!

Thanks for sharing it.
10:41 pm
Chris Ballard said…
I like how you've been using 3 stepper motors for your project. I've been learning about how they work and it's interesting to see more practical applications.
8:19 pm
misan said…
Thanks Chris.

I've got a detailed description published on Circuit Cellar magazine #212 and there is a
better video of the system in here

BTW, please note that this configuration has quite weird math background (non-linear differential equations) so it is not used very often.
9:15 pm
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