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.)
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.