n

1. Product Specifications
Teaching materials to accompany:
Product Design and Development
Chapter 6
Karl T. Ulrich and Steven D. Eppinger
5th Edition, Irwin McGraw-Hill, 2012.

2. Product Design and Development
Karl T. Ulrich and Steven D. Eppinger
5th edition, Irwin McGraw-Hill, 2012.
Chapter Table of Contents:
1.Introduction
2.Development Processes and Organizations
3.Opportunity Identification
4.Product Planning
5.Identifying Customer Needs
6.Product Specifications
7.Concept Generation
8.Concept Selection
9.Concept Testing
10.Product Architecture
11.Industrial Design
12.Design for Environment
13.Design for Manufacturing
14.Prototyping
15.Robust Design
16.Patents and Intellectual Property
17.Product Development Economics
18.Managing Projects

3. Concept Development Process
Perform Economic Analysis
Benchmark Competitive Products
Build and Test Models and Prototypes
Identify
Customer
Needs
Establish
Target
Specifications
Generate
Product
Concepts
Select
Product
Concept(s)
Set
Final
Specifications
Plan
Downstream
Development
Mission
Statement Test
Product
Concept(s)
Development
Plan
Target Specs
Based on customer needs
and benchmarking
Final Specs
Based on selected concept,
feasibility, models, testing,
and trade-offs

4. 06/18/18 4
Outline
• Nature of specifications
• Spec vs. specs.
• Target vs. final specs.
• Process for setting target specs
• Process for setting final specs

5. 06/18/18 5
Spec vs. Specs
• A spec consists of a metric, a unit, and
a value
• Specs has a set of specs.

6. 06/18/18 6
Target vs. Final Specs
• Target specs: the hope and aspiration
of the design (ideal and marginal)
• Refined specs: trade-offs among
different desired characteristics.
– Intermediate specs
• Final specs
– It is in the project’s contract book

7. 06/18/18 7
Nature of Specifications
• The reference point for functionality
design and quality planning
• A product assembly usually requires a
hierarchy of specs, for the final product
and each of its components

8. The Product Specs Process
1. Set Target Specifications
– Based on customer needs and benchmarks
– Develop metrics for each need
– Set ideal and acceptable values
1. Refine Specifications
– Based on selected concept and feasibility testing
– Technical and economic modeling
– Trade-offs are critical
1. Reflect on the Results and the Process
– Critical for ongoing improvement

9. 06/18/18 9
Procedure for establishing
target specifications
1. Identify a list of metrics and measurement
units that sufficiently address the needs
2. Collect the competitive benchmarking
information
3. Set ideal and marginally acceptable target
values for each metric (using at least, at
most, between, exactly, etc.)
4. Reflect on the results and the process

10. 06/18/18 10
Process for setting the final
specifications
1. Develop technical models to assess technical feasibility. The
input is design variable and the output is a measurement using
a metric.
2. Develop a cost model of the product.
3. Refine the specifications, making tradeoffs, where necessary to
form a competitive map.
4. “Flow down” the final overall specs to specs for each
subsystem (component and part).
5. Reflect on the results to see
 Whether the product is a winner, and/or
 How much uncertainty there is in the technical and cost model, or
 Whether there is a need to develop a better technical model.

12. Product Specifications Example:
Mountain Bike Suspension Fork

13. Start with the Customer Needs

14. Metrics Exercise:
Ball Point Pen
Customer Need:
The pen writes smoothly.

15. Establish Metrics and Units

16. Link Metrics to Needs

17. Benchmark on Customer Needs

18. Benchmark on Metrics

19. Assign Marginal and Ideal Values

20. Concept Development Process
Perform Economic Analysis
Benchmark Competitive Products
Build and Test Models and Prototypes
Identify
Customer
Needs
Establish
Target
Specifications
Generate
Product
Concepts
Select
Product
Concept(s)
Set
Final
Specifications
Plan
Downstream
Development
Mission
Statement Test
Product
Concept(s)
Development
Plan
Target Specs
Based on customer needs
and benchmarking
Final Specs
Based on selected concept,
feasibility, models, testing,
and trade-offs

21. Perceptual Mapping Exercise
Chocolate
Crunch
Hershey’s
w/ Almonds
Hershey’s
Milk Chocolate
Nestlé
Crunch
KitKat
Opportunity?

24. 06/18/18 24
Specification Trade-offs
.
Score on Monster (Gs)
EstimatedMfg.Cost($)
50
60
70
80
90
100
110
120
3 3.2 3.4 3.6 3.8 4
Gunhill Head
Shox
Tonka Pro
Rox Tahx Ti 21
Rox Tahx Quadra
Maniray 2
ST Tritrack
marginal values
ideal values
Score on Monster (Gs)
Trade-off Curves
for Three Concepts
EstimatedManufacturingCost($)

25. Set Final Specifications

26. Quality Function Deployment
(House of Quality)
technical
correlations
benchmarking
on needs
customer
needs
engineering
metrics
target and final specs
relative
importance
relationships between
customer needs and
engineering metrics

28. 06/18/18 28
Profit margin
Where:
M: profit margin
P: price
C: cost

29. 06/18/18 29
Target Cost
Where:
C = target cost
P = price to the end user
Mi = the margin at the ith stage.

30. 06/18/18 30
Mark up
Markup = P/C - 1
Where:
P: price
C: cost

32. 06/18/18 32
Chapter 6 HW
Metric Exercise: Ball Point Pen
 Identify five possible metrics and the unit of measure for a customer
need as stated below:
The pen writes smoothly.