Ekras

I will send you a pm

I guess this answer is a bit to late. But I might be able to help you now, but you will have to provide me with a bit more information about what you have done and what isn't working.

Lovely, always fun to see pictures of other peoples work :)

I got 2 black pieces of tape, taped to the top and bottom of the curtain. The arduino keeps track of where it is, so it always knows in what state it's in (up/down) it will therefor always starts rolling in the right direction. It knows that it has successfully changed it's state when the light sensor sees the black tape, the arduino stops the motor and also makes changes in it's memory to correspond to the new position.short: Keep track of position in memory, knows that it's done rolling up when the sensor triggers.