The idea for this project came when after having to open and close the shades in my room manually, and having them frequently get caught or not being able to close them all the way. I discovered that if you pull the shades from the top, parallel to the curtain rod, then they almost always open without getting caught and require much less force to open. Below is my system of using ropes, pulleys, and an arduino to automate the shades opening in the morning when I want to wake up.
The diagram to the right describes the exact set up of the ropes and pulleys, blue dots are where the rope feeds through the pulleys (pictures below), and yellow dots are where the rope is tied to the curtain. The lowest blue dot is the pullet that maintains tension on the system, and all the other pulleys are connected to the curtain rod. Pull the rope one way and it pulls the two yellow dots apart, opening the curtain, and pull it the other way and the two yellow dots are pulled together, closing the curtain.
Here is a picture of one of the pulleys I used. I ordered them off of amazon, and when they came they were much smaller then I had imagined. Make sure the pulley and rope can fit together
The two pulleys on the left side of the drawing:
The pulley in the middle: