What Constraint would I use to Bend or Rotate a Part Down

INTRODUCTION

I’m Currently working on Creating my First Fair Ride!
I’m trying to Figure out What Contraints in a Situation like this.
I’m trying to bend/lower the Arms of the Swing using a Constraint
And I’m having a really hard time seeing which 1 to use.

SCREENSHOTS

Motors, hinges, or servos. Either works, just depends on what you’re trying to do

Thanks this is just what I needed!