Chapter Table of Contents
2. Development Processes and Organizations
3. Product Planning
4. Identifying Customer Needs
5. Product Specifications
6. Concept Generation
7. Concept Selection
8. Concept Testing
9. Product Architecture
10. Industrial Design
11. Design for Manufacturing
13. Robust Design
14. Patents and Intellectual Property
15. Product Development Economics
16. Managing Projects
Product Development Process
Concept System-Level Detail Testing and Production
Planning Development Design Design Refinement Ramp-Up
Prototyping is done throughout the development process.
Concept Development Process
Statement Identify Establish Generate Select Test Set Plan Plan
Customer Target Product Product Product Final Downstream
Needs Specifications Concepts Concept(s) Concept(s) Specifications Development
Perform Economic Analysis
Benchmark Competitive Products
Build and Test Models and Prototypes
Apple PowerBook Duo Trackball
Four Uses of Prototypes
– answering questions about performance or
– e.g., proof-of-concept model
– demonstration of product for feedback
– e.g., 3D physical models of style or function
– combination of sub-systems into system model
– e.g., alpha or beta test models
– goal for development team’s schedule
– e.g., first testable hardware
Types of Prototypes
ball alpha beta
support prototype prototype
linked to circuit
Focused simulation Comprehensive
Physical vs. Analytical Prototypes
Physical Prototypes Analytical Prototypes
• Tangible approximation of • Mathematical model of the
the product. product.
• May exhibit unmodeled • Can only exhibit behavior
behavior. arising from explicitly
• Some behavior may be an modeled phenomena.
artifact of the (However, behavior is not
approximation. always anticipated.
• Often best for • Some behavior may be an
communication. artifact of the analytical
• Often allow more
experimental freedom than
Focused vs. Comprehensive Prototypes
Focused Prototypes Comprehensive Prototypes
• Implement one or a few • Implement many or all
attributes of the attributes of the product.
product. • Offer opportunities for
• Answer specific rigorous testing.
questions about the • Often best for milestones
product design. and integration.
• Generally several are
Many comprehensive Some comprehensive
prototypes are built. prototypes build (and sold?).
Technical or Market Risk
One prototype may be Few or no comprehensive
used for verification. prototypes are built.
Cost of Comprehensive Prototype
• Use prototypes to reduce uncertainty.
• Make models with a defined purpose.
• Consider multiple forms of prototypes.
• Choose the timing of prototype cycles.
–Many early models are used to validate
–Relatively few comprehensive models are
necessary to test integration.
• Plan time to learn from prototype cycles.
–Avoid the “hardware swamp”.
Rapid Prototyping Methods
• Most of these methods are additive,
rather than subtractive, processes.
• Build parts in layers based on CAD
• SLA=Stereolithogrpahy Apparatus
• SLS=Selective Laser Sintering
• 3D Printing
• LOM=Laminated Object Manufacturing
• Others every year...
• 3D CAD models enable many kinds of
– Fit and assembly
– Form and style
– Finite element analysis (stress, thermal)
– Crash testing
– more every year...
BMW Virtual Crash Test
From: Scientific American, March 1999
Traditional Prototyping Methods
• CNC machining
• Rubber molding + urethane casting
• Materials: wood, foam, plastics, etc.
• Model making requires special skills.