Instead of explaining how it works... build one yourself, and try it out!
Instructions!
Pieces needed:
Build this first:
Then this (don't forget the ball joints!):
Add four of those greens (why do I even have this step?
):
Add that last yellow, and the two greens in between...:
And that's it!
To make the seats go up and down, I'd suggest putting a small connector on the ends of the yellow rod in the last step, and put something near the walls of the station that push it down when coming in, and push it up when leaving the station. I don't feel like making a station now, though.
