The prototype ladder
- Proof of concept: breadboards and off-the-shelf electronics confirm a function works at all, at low cost and in days.
- Works like, looks like (WLLL): a build that looks and behaves like the final product, so you and your users can handle something close to the real thing. Once it has been costed with manufacturers and tested with real users it is your Market Validated Prototype (MaVP).
- Pre-Manufacture Prototype (PMP): built from production data and approved before tooling capital is committed.
Each prototype tests a specific assumption, and each lesson goes back into the design while change is still cheap. By the time tooling is cut, what is left to check is the tooled part against the design (the Final Engineering Prototype), not the design itself.
For the general approach to prototyping any product, see how do I make a prototype of my idea.