Plotter made from scrap computer parts

Our old friend HomoFaciens (who has the best voice of any Raspberry Pi user we’ve met) has another fantastic piece of work to share. He’s recycled old optical drives for their stepper motors, and made a tiny plotter, controlled over WiFi, from those motors, a servo, four H-bridges and a Raspberry Pi.

HF has made a full writeup, including all the source code you’ll need, available at his website. As always, he’s also made the whole video and writeup available in German. HomoFaciens’ website is one of those bits of the internet you’ll find yourself wandering around for ages if you’re even slightly interested in this sort of thing. He’s got some fascinating stuff on there; I heartily recommend giving one of his camera-equipped robots a spin via the web interface they’re hooked up to. (No prizes for guessing which is my favourite.)

Screen Shot 2015-04-24 at 13.02.15

If you decide to make your own plotter, be aware that not all old optical drives have stepper motors – HomoFaciens’ hit rate was about 50% when he started pulling them apart.


HomoFaciens avatar

I was wondering why the traffic on my page boomed over the last few hours – looks like I found the reason. Thanks for promoting my project and if you like the tiny Raspberry powered robot, you might also have a look at my biggest one (jump to time index 50:19 to see R.I.T.T = Raspberry Intelligent Transportation Technology):


Liz Upton avatar

Thank you Norbert – as you’ve probably gathered, we’re big fans!

HomoFaciens avatar

….become more than just fans – support me. I need a lorry full of Raspberry Pis, servos, transistors, LEDs and so on (e.g. photovoltaic cells would be nice to keep the running costs of my RoboSpatium low) to turn the ideas in my had into something physical.

Thanks again for the promotion work – my project gathered a lot of publicity over the past days.

heath avatar

I’ll be back…with a Steppa Motah!

HomoFaciens avatar

…don’t kid the master of robots – you might get terminated ;)

Ben Shamsian avatar

Awesome projects Norbert, love all of them

mahjongg avatar

Very creative!
A “plot on any surface portable device” sounds like something that has a lot of potential!

and prototyped with a raspberry PI and some spare parts, what could be better. :-O

HomoFaciens avatar

Feel free to turn it into money ;)

Dougie avatar

Superb, well worth the 6’47” watching that one.

Bill Stephenson avatar

This is really cool!

I was rummaging around my workshop and found an old Radio Shack DIY circuit board kit. It contains a felt tip marker that looks like a “Sharpie” and a copper coated board about 4″x4″, a bottle of etching solution, and a bottle of ink remover.

You draw your circuit lines on the board then strip the copper around them with the etching solution. Then drill holes, remove the ink, and solder in your components.

I don’t know if they still sell these kits anywhere, but I got to thinking while looking at it how you might draw your line with a pair of old inkjet printers cartridge drives set up in a similar way to drive the pen like HomoFaciens does here. This does exactly what I was thinking about.

Anyway, I love this project, it’s just cool as can be and I want to make one! (My old kit won’t work anymore. All the solvents evaporated long ago. The pen still works though!)

Jim Manley avatar

Hey Bill! Have the raptors … I mean mosquitoes … in the Ozarks started their human-hunting expeditions yet? :D

I assume you must be acquainted with the technique of printing a circuit board pattern backwards on a Mylar overhead projector transparency sheet, then laying it ink-side toward a photo-sensitive coated PC board, exposing the sheet-covered board to the Sun or other intense UV source, rinsing and immersing the board in etchant, rinsing again, and removing the resist layer from the remaining copper circuit traces. Not as much fun to watch as a robot pen, but it works.

Be looking for the portable Raspberry Office Computing Kit (ROCK) in a blog post near you soon!

HomoFaciens avatar

…watching the pen drawing lines is indeed funny!
A homemade printer will follow some day – maybe that will be a better solution.

Bill Stephenson avatar

Jim, I learn something from you whenever our paths cross!

I’ve been almost as busy as you these past few months. Been having a blast learning about some new web app tools and setting them up on my Pi. I’m going to try and put together a new disc image for the office kit, but now you’ve really peaked my interest in what you’ve been up too!!!

I’ll make a point to take the time to fill you in on what I’ve been doing soon…

Mark Daniels avatar

I still have an 8 inch floppy drive lying around with a rather large stepper motor or two in it. I wonder … ;)

wallyware avatar

I want to adapt this to my new MOTORplate:

amin seraj avatar

Very very nice. thank you for your idea

Satyadev avatar

Cool DIY and Nice explanation.

Sridhar G avatar

Nice job man.. Very impressive

ColinD avatar

I really like projects like this that use otherwise redundant and destined-for-recycling components. It reminds me in some ways of the music made with old floppy disk drives.

HomoFaciens avatar

Old computers are a great resource for mechanical parts usable for some physical computing.

Comments are closed