You can get Arduinos CHEAPER when not ordering inside the US actually..
look on ebay.
I got a pro mini a few days ago for like $3-4 bucks or something..
IMHO.. the time it will take you to read up on a pulley system.. you could also learn the basics of Arduinos..
There are so many tutorials.. it will be easy. (Its a huge community)
The servo you use will depending the 'weight' of the flap really..
there are many many Iron Man/Arduino tutorials out there.. (I posted one on motorizing an Iron Man bucket even.. that uses servos)
why no go -all out- for yoru build and include electronics!?
