A functional prototype is a physical version of a defined or partly defined design, made so you can learn from the part before deciding what comes next. Handle it, review how it fits with related parts and how it behaves during assembly, and use those observations to identify possible design changes.
It is not necessarily the final production part. Its purpose, material and manufacturing route may differ from a later production part.
When a functional prototype is useful
A prototype can be useful when the design needs to be understood beyond the screen. It may support:
- reviewing fit and interfaces against the available mating information
- seeing how parts interact during assembly
- handling a physical version of the geometry
- comparing geometry options side by side
- observing practical usability in the intended context
- identifying possible design changes before the next project stage
The prototype creates a practical basis for review; it does not guarantee a particular result. The useful question is what the physical version helps you notice and decide.
What a prototype can help reveal
Working with a physical part can bring attention to mismatches between related components, awkward interfaces, assembly issues or geometry that needs adjustment. It can also surface observations about handling, access, orientation and practical usability that are difficult to assess from CAD alone.
These observations can guide the next design decision. Where useful, Stage 13 can make CAD changes after the review and produce one or more additional physical iterations. Each additional iteration is scoped separately around the project objective and the changes being considered.
The prototype supports practical review and design decisions before the next project stage. Any later production step is evaluated and scoped separately.
From CAD to physical iteration and the next decision
The development path stays focused on the learning objective:
- Define what you want to learn and identify the available inputs.
- Review the CAD or design and the relevant interfaces.
- Produce the physical prototype using an appropriate route. Industrial 3D printing may be considered when suitable for the prototype objective.
- Review the prototype and what you learned from it.
- Update the CAD or make another prototype if useful, with each iteration separately scoped.
- Evaluate the next manufacturing or production step as a separate project decision.
Choose your starting route
A. You already have usable CAD, a drawing or a defined design
Send the available file and relevant project information for technical review. Include the prototype objective, interface details, critical dimensions and use conditions where available.
B. You still need design or CAD work, or you have requirements or a concept only
Start with a conversation about the objective, available references and the design decisions still open. If the geometry needs to be created, adapted or developed before the physical iteration, see CAD Design for Custom Parts.
When the objective or design scope is still open:
When you already have a file ready for technical review: