Let's Make Robots!

mechanical

Walks down slopes using gravity, makes his owner smile.
Wobbly is a 3D-printed, gravity-powered, walking automaton. He basically walks down slopes. Read more

Antique desk, marvel of engineering

http://www.youtube.com/embed/MKikHxKeodA?rel=0

I can't even imagine the time it took to design & build something like this. All done with no electricity, motors, or micros.

How to pull on a fishing line

I'm making some simple motorized (but small) clothing accessories, and part of it is actuated by pulling on a length of fishing line. I'm trying to figure out the best way to do that. I was thinking a little spool, but there are some problems. The fishing line could go slack if the part is pushed on, and I need the line to not unspool. Second is that it needs to be really small... the closer to about a half centimeter (from flange to flange), or less, the better. I'm having a hard time finding something that small. Is there some better way than a spool?

Any good mechanical engineering books?

I just finished reading this: http://www.allaboutcircuits.com/. It really helped me understand all the electronic background of robotics. Now I feel like reading about mechanical engineering so does anyone have a good book or website to recommend? 

Sprockets and Gears

Where are some good online stores to buy sprockets, gears, etc. from? In small and large sizes.

Thanks-Magykguy721

Incredible wooden mechanical machines video

Have a look at the engineering that has gone into some of these machines. I especially like the gearbox mechanism on the 2nd video to change from raising to extending the arm.