Product Prototyping
Prototyping is the rigorous process of building physical models to answer specific questions about form, function, and feasibility.
Product Prototyping
(Learning Before Investing)
Definition (Canonical)
Product prototyping is the iterative process of building physical models to answer specific questions about a product’s form, function, or feasibility.
Prototyping is risk reduction. It is the only way to validate assumptions before committing to expensive production tooling (molds, dies, and fixtures).
The Purpose of a Prototype
A common misconception is that a prototype is just a “draft” of the final product.
In reality, smart teams build different prototypes for different questions:
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"Does it fit?" (Looks-Like) Checking size, ergonomics, and aesthetics. Tools: Foam core, 3D printing, clay, urethane casting.
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"Does it work?" (Works-Like) Checking mechanism, electronics, thermal performance, or physics. Tools: Breadboards, machined metal, ugly fabricated rigs.
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"Can we make it?" (Pre-Production) Checking assembly steps, part tolerances, and manufacturing flow. Tools: Soft tooling, CNC, rapid injection molding.
A prototype that tries to answer all these questions at once is usually expensive, slow, and compromised.
Prototyping Fidelity Stages
The industry uses standard terms to describe prototype maturity:
1. Proof of Concept (PoC)
Often ugly and tethered to a bench. It proves the core science or mechanism works. Goal: Violate no laws of physics.
2. Looks-Like / Cosmetic Model
A non-functional shell that looks exactly like the final product. Used for investor pitches or photo shoots. Goal: Sell the vision.
3. Works-Like / Engineering Prototype
Functional internals, often in a non-final enclosure. Used for lab testing. Goal: Prove reliability.
4. Engineering Validation Test (EVT) of "Alpha"
The first attempt to combine "looks-like" and "works-like." Built with intended materials but often soft tooling. Goal: Identify integration issues.
5. Design Validation Test (DVT) of "Beta"
Built using final production processes (e.g., injection molding). Goal: Validate manufacturing quality and regulatory compliance (FCC/CE).
Common Prototyping Traps
1. Over-Finishing Early
Spending thousands of dollars painting and sanding a model that is going to change next week. Form verification should be rough and fast.
2. Misinterpreting 3D Printing
3D printing is amazing, but it hides design flaws. It has no draft angles, uniform wall thickness requirements, or assembly clearance constraints. A part that 3D prints easily may be impossible to mold.
3. Skipping the "Ugly" Phase
Teams that rush to making it look pretty often find out too late that the battery doesn't fit or the antenna is blocked by metal.
Why Physical Prototyping Can't Be Skipped
Simulation and CAD are powerful, but they miss real-world variables:
- How a button "feels" (force displacement curve).
- How cables route and bend inside a tight enclosure.
- How users actually hold the device vs. how you imagined they would.
- Unexpected thermal hotspots.
You cannot feel quality in a render.
Related Concepts
- Physical Product Development
- Industrial Design
- Design for Manufacturing (DFM)
- Hardware–Software Integration
Build to think.
Explore Related Topics
Design for Manufacturing (DFM)
Design for Manufacturing (DFM) is the engineering discipline of optimizing a product design so it can be mass-produced efficiently, reliably, and cost-effectively.
Hardware–Software Integration
Hardware-software integration is the coordination of physical constraints (sensors, battery, chips) with digital logic (firmware, cloud, app) to create a seamless user experience.
Industrial Design
Industrial design (ID) defines how a physical product looks, feels, and functions for the human who uses it, bridging the gap between human needs and technical feasibility.
Physical Product Development
Physical product development is the process of designing, engineering, validating, and manufacturing tangible products that must exist reliably in the real world.
Product Strategy for Physical Products
Product strategy for physical goods requires balancing user desirability, technical feasibility, and business viability—factoring in BOM costs, retail margins, and inventory risk.