These x-ray machines look inside a piece of equipment, allowing operators to verify assembly and to inspect for material integrity. It also allowed [Nico71] the opportunity to scan a LEGO servo he ...

So, what is an LDU precisely? It’s the smallest incremental size used to define LEGO’s dimensions. For context, a standard LEGO brick is 20 LDUs wide, and a single plate is 8 LDUs tall.