Circle Combination Lock

Hi,
I'm fairly new to using unity and I'm designing a 2D puzzle game. I am trying to figure out how I would go about coding a circle combination lock similar to the Golden Claw puzzle in skyrim (for those that have played it). The basic concept is that you have several circle layers and they all need to match up to a specific pattern or pre-decided layout in order for the door to open. However, I've poured through the forums for a while now and I can't find anything remotely similar or a tutorial of anything close to the mechanics of what I would need. Anyone able to point me in the right direction? If someone has already posted something like this that I couldn't find, I apologize. Please let me know.

 

Break this down into smaller steps.

You need:

• A set of concentric sprites
• A way to rotate the sprites to set positions
• A way to figure out which position each sprite is in
• A way to match the current position of all sprites with the target position

If these steps are too challenging, break each one down into smaller steps.