Hi! 
Easy way to do this, since it just rotates on a hinge, is to use a drag. If the drag is moved up, turn the circle counter-clockwise. If the drag is moved down, turn the circle clockwise.
The problem is that the circle goes through infinity, where as a drag to control the timeline needs a start and ending point. (I'm not sure if restarting the timeline works with dragging.)
If that doesn't work, you could just use JavaScript and math… kinda like the eyeballs in the “Looking” template…
…instead of an event based on the mouse move, maybe it could be a Hype drag event… possibly similar to the discussion here…
@h_classen solved the problem by using a drag event. I was thinking an element had to be moved around for the drag to work, but no. It works just fine with a group.
It looks like your bridge is not that far… less like the Verrazano, more like the Brooklyn Bridge. 