Stepper motors are used for high precision motion, like that needed for 3d printers and CNC machines. The Learn Engineering channel on YouTube explains how they work.
Tag: engineering
Appropriate Technology: Innovation with Light
Not a lot of light penetrates the galvanized steel roofs that are ubiquitous in slums around the world. Alfredo Moser came up with one ridiculously cheap solution (via the World Social Forum, 2011).
While this the kind of cheap, elegant solution I would go for in a heartbeat, I’m pretty sure my wife would veto. For the more stylistically conscious – and for people with a bit more money in their pockets – there are $2.00 LED lights advocated by The Appropriate Technology Collaborative (ATC). A lot of people in dire poverty live in the slums, but that’s not the case for everyone.
The ATC’s seems to focus on projects designed by university students and implemented in the third world. If they work, the designs are published with a Creative Commons license so that other Non Governmental Organizations (NGO’s) that work in poorer countries can use and distribute them. Their blog has a lot of good information. And, there’s also the Global Bucket project that I’m still keeping an eye on.