NTRAF section 2 and section 3.5 / Prototype development

What TRL 4 means

Basic technological components are integrated to establish that they will work together. TRL 4–6 is the bridge from scientific research to engineering.

Criteria reviewers look for

• Available components work together in a lab setup.
• Key manufacturing processes are identified.
• Low-fidelity system integration has been completed.

Evidence examples

• Component validation report
• Breadboard test report
• Preliminary FMEA

Next action

Move from a lab setup to a higher-fidelity prototype with realistic interfaces.