创意机械艺术币设计

I have always been a fan of Roman Booteen's coins. Can Nano Banana Pro come up with something similar? Let's see.
Prompt:
Step 1: Research Roman Booteen's best mechanical art coins
Step 2: come up with 4 next-level new ones that are not a copy of anything done before
Draw 2x2 grid: each panel with a new mechanical art coin, explain the mechanism below each