Here's the initial design, but I'm open to suggestions:
All file names start with the prefix "ops_".
Each subsequent term added to the prefix is an identifier that relates all files with matching prefixes.
For example, "ops_schematic_led.png" and "ops_schematic_pot.png" are related because of the "opsschematic" prefix. This means they must both be schematics
Here's the initial design, but I'm open to suggestions: