The above contraption is a combination of 2 simple machines – a pulley system and a a ramp/lever. When pulling the string down on the right, the left side will rise up, pulling the connected ramp/lever with it. The ramp will rotate along the fulcrum, and finally, the left side of the ramp will make contact with the ground while the right side will be lifted in the air. The load (the pen cap) will then slide down.
My final product is actually almost identical to my original plan. In the original plan, I had already thought about how to make the pulley system and already designed my product to be able to accommodate my pen. However, due to the flimsiness of the cardboard, I had to stick two cardboard pieces together so that it would be strong enough to hold the weight of my pen. Other than that, the only other change was with ramp/lever. Originally, I was planning to use a larger ramp/lever, but since I ran out of time, I could only use one of the old pieces I cut to make the ramp.
In the video, you will notice the cap struggling to slide down. This is because of 1) the ramp is not very steep and 2) the cap does not have much mass, therefore affected by gravity a lot. I could find an item that is heavier/has more mass since the flimsy ramp would not be able to support it.