As examples:
For a customer that manufactured exhaust systems for small aircraft, I would take a pieced together tubing prototype in the shape of the exhaust header and muffler system, then measure and working with toolmakers, tubing vendors, and FAA and determine how the part could be manufactured and provide drawings for FAA compliance and approval.
In the Electronics arena, taking "bread board" circuit and tracing the connection nodes, generating schematics and interconnection diagrams, then producing PCB and packaging as required.