for 15 cps, I'd make that rod operate as a plunger in a solenoid.
You could either buy or scavenge one (out of an old pinball machine, doorbell or dozens of other things), or if you did the math you could wind your own. It's just a simple spool of wire - the tricky thing would be figuring out the number of winds for the wire gage and voltage you want it to operate at.
Anyway, it would just slide to one side when voltage was applied, then a spring would slip it back to "rest" position.
Layman's terms. I'm no expert.