Transcript Lecture 7 Concept Selection

• Last Homework assignment
− Complete the FSD. Due Today. Put on
website and email a copy to me.
− Work on the Concept Generation portion of
the CG&S Document for your Project.
− Email me with ~5 concept fragments for
your actual project. We will discuss these
in class on Tuesday.
− Read Chapter 7, Concept Selection in Ulrich
and Eppinger
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Team Pythagoreans:
Jonathon Taylor
Daniel Richins
Jim Meaders
Ryan West
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Lecture 7 Concept Selection
Decision Making 101
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Concept Development Phase
Phase 1
Concept
Development
Phase 2
Phase 3
System-Level
Detail
Design
Design
Phase 4
Testing and
Refinement
Phase 5
Production
Ramp-up
Mission
Statement
Identify
Customer
Needs
Development
Plan
Establish
Target
Specs
Generate
Product
Concepts
Select a
Product
Concept
Test
Product
Concept
Set
Final
Specs
Plan
Downstream
Development
Perform Economic Analysis
Benchmark Competitive Products
Build and Test Models and Prototypes
Concept Development
Exhibit 2 Chapter 3 Ulrich & Eppinger
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Iterative Process of Screening and
Scoring
Filter and decide
Concept generation
Concept screening
Concept scoring
Concept testing
Expand our thinking
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• Every team uses some method of decision making.
Common methods include:
− External decision; let someone else decide, customer,
client, etc.
− Product Champion; an influential team member chooses
the concept.
− Intuition; subjective criteria are used to decide. It just
feels better.
− Multi-voting; team members vote for their favorite.
− Pros and Cons; team list strengths and weaknesses and
choose based on opinions.
− Prototype and test; team builds several units and decision
is based on results.
− Decision matrices; team rates each concept against
defined selection criteria.
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• Benefits of using decision matrices
− A customer focused approach; concepts are
evaluated against customer-oriented criteria.
− More competitive designs; concepts are
benchmarked against best-in-class designs.
− Reduced development time; using a structured
approach develops a common vision and language
for the design team.
− Better group decision making; the decision is
more likely to be based on objective criteria.
− Documentation of the decision process; the
method provides its own documentation.
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Caution
• Concept Scoring and Screening matrices are
only used on those few (less than 5) design
problems that will make a significant
difference in the outcome of your project.
• You don’t need the formality of concept
scoring and screening for obvious design
choices or those that are dictated by the
preferred solution.
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• The Two Stages of Concept Selection
− Concept Screening: give relative score against
a known benchmark design.
− fast, approximate evaluation that produces several viable
concepts.
− Best used when quantitative comparisons are difficult.
− Usually requires some sort of reference concept for relative
evaluation.
− Concept Scoring: weighted ranking of
measurement criteria.
− Used when only a few alternatives are being considered.
− Required quantitative comparisons of concepts.
− Can still be quite subjective due to choices of weights and
ranks.
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• In both cases we use the Six Steps of
Concept Selection
− 1. Prepare the selection matrix—choose the
selection criteria.
− 2. Rate the concepts. Evaluate against a reference
− 3. Rank the concepts. Give the concept a # score
− 4. Combine and improve concepts.
− 5. Select one or more concepts.
− 6. Reflect on the results and the process.
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Method 1--Concept Screening
Product Concepts
Selection Criteria
A
B
C
E
F
Criteria 1
Criteria 2
Criteria 3
Sum/Rank
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Concept Screening
Concept Ratings
Concepts
A
B
C
E
F
0
-
0
+
--
Criteria 2
0
-
+
++
0
Criteria 3
0
0
-
0
-
0
-2
0
+3
-3
Criteria
Criteria 1
Sum/Rank
A= reference
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• Step 1--Preparing the Selection Matrix.
− The choice of the selection matrix is key to
the success of both Screening and Scoring.
− Selection criteria should be independent.
− Selection criteria should be chosen to
differentiate among the concepts.
− The criteria should be of the same relative
worth.
− Don’t get too many criteria.
− Use industry comparisons if available.
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• Concept Screening matrix
− Start with the selection criteria.
− Where are you going to get the selection
criteria?
− These are the key attributes or features of
the product as determined in the FSD.
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• Next develop the list of concepts that you
are considering for the solution
− This list is the output of the concept generation
exercise.
− Prune the list using intuitive methods to a
manageable number of concepts to consider.
− Each concept should be a solution to the same
problem.
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• Concept Screening
− Step 2--Rating Concepts
• Use a relative score, +, 0, - or colored dots
• rate against a reference
− Step 3--Rank the Concepts
• sum up the scores
• rank the concepts by scores, highest to lowest.
− Step 4--Combine and Improve the Concepts
• Look at the results and see if there are ways to
combine concepts
• is there one bad feature that is degrading a good
concept?
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In-Class Exercise
• Your team is working for “Innovative Directions”
• You have been given the assignment to work with BYU on
a special project.
• Your team has been assigned this task:
•
“Design and build an economical solution which will
make it easy for those unfamiliar with the BYU campus
to find their way around.”
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Innovative Directions Concept Generation
What would be some of the possible solutions for
providing campus directions?
•Physical map
•Downloadable map
•New signs on campus
•New building signs
•Color coded strips on the sidewalks
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Innovative Directions Concept Screening example
What would some good screening criteria for
choosing the best alternative for the Innovative
Directions example?
Criteria
• Cost of the solution
• Ease of use
• Portability
• Accuracy of data
• Cost of development
• Availability of solution
What would be a good benchmark concept?
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Color coded stripes
on walks
New building signs
New signs on campus
Downloadable Map
Criteria
Physical Map
Concept Screening
Concepts
Ease of
Use
Availability of
information
Cost
Sum/Rank
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• Concept Screening continued
− Step 5--Select One or More Concepts
• Look for patterns and groupings of concepts.
• Look for natural breakpoints among concepts.
− Step 6--Reflect on the Results
• try to get consensus among the team on the
results.
• Ask if the criteria reflects the critical customer
needs.
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• Method 2--Concept Scoring
− Step 1--Preparing the selection matrix.
− In addition to the requirements for
screening:
• each criteria must be assigned a weight in
relationship to its importance.
• A good way of assigning weights is to allocate
100 percentage points across all criteria.
• Or, importance values can be assigned, 1-9.
• There are empirical methods of assigning
weights, but more often they are determined by
team consent.
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• Concept Scoring Matrix
Concepts
Concept A Concept B Concept C Concept D
Criteria
Weight
Criteria 1 X%
Criteria 2 Y%
Criteria 3 Z%
Totals
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100%
Rating Weighted
Score
1
3
9
Rating Weighted
Score
Rating Weighted
Score
Rating Weighted
Score
1X
3Y
9Z
Sum
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• Concept scoring, continued
− Step 2--Rate the Concepts
• assign a numerical value to each concept with
respect to the criteria.
• Use a wide scale to help differentiate among
concepts. I.e. 1,3,9
− Step 3--Rank the Concepts
• ranking is done by multiplying the concept
scores by the criteria weights.
• Add up all the scores for each concept.
• List the concepts by descending order.
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Methods of PDA<->Computer Communication (Hardware)
Power consumption (Weighted x 1)
4x3=
6x2=
4x1=
4x1=
2x1=
4x1=
12
12
4
4
2
4
0x3=
4x2=
6x1=
6x1=
6x1=
4x1=
0
8
6
6
6
4
6x3=
0x2=
2x1=
4x1=
6x1=
4x1=
18
0
2
4
6
4
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Customization of PDA necessary?
(Weighted x 1)
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Ease of communication programming
(Weighted x 1)
IrDA
Reliability (Weighted x 1)
Wireless LAN (802.11)
Communication Distance (Weighted x 2)
Serial Radio Link (One on each side)
Cost (Weighted x 3)
0 = Terrible
2 = Decent
4 = Good
6 = Awesome
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• Concept Scoring continued
− Step 4--Combining and improving is similar to
concept screening.
− Step 5--Select one or more concepts
• choose the highest ranking concepts
• look for individuals scores where one criteria was
significant to the total.
• Decide whether the scoring was quantitative enough
to make a decision.
− Step 6--Reflect on the Results
• this is again similar to screening, does the answer
make sense.
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• In class exercise
− Develop a scoring matrix for the criteria
that you developed in Exercise #1.
− Give relative weights to the criteria and
design a scoring definition for the ranking.
− How does this help with the evaluation of
the criteria?
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Availability of information
0
Cost
0
Sum/Rank
0
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0
0
walks
0
Color coded stripes on
New building signs
0
New signs on campus
Ease of use
Downloadable Map
Weight
Concept Scoring
Physical Map
In class exercise
0
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• Potential problems
− Concept criteria are not independent
• a set of criteria reflects a common need,
resulting in too heavy a weighting.
• For example, if you had three criteria relating to
quality, and only one relating to cost, the sum of
the quality scores would be spread over three
criteria, while cost is concentrated in one
criteria.
− Criteria are too subjective. How do you
deal with subjective criteria?
− Cost must always be included in some form,
because of the importance to the customer.
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• Summary
• All teams use some form of selection, often it is
implicit and unstructured.
• Structured concept selection provides a level of
objective measurement that can help differentiate
between competing solutions.
• Concept screening is useful for eliminating alternatives
when you have a large number to consider.
• Concept scoring is used to refine the selection when
you have only a few choices.
• Screening and scoring are not exact sciences.
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• Homework
− Complete the Concept Generation and
Scoring Document. Due at design review
next week.
− Be sure to cover all 5 of areas of the
decision Matrix to insure that the reader will
understand your thought process, and
especially the assumptions that you are
using. (see the document description on the
ECEn 490 business website.)
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Physical Map
Downloadable Map
New signs on campus
New building signs
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5
5
6
4
6
Availability of information
40
5
7
4
4
5
Cost
20
5
7
3
2
3
100 500 620 460 360
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Weight
Ease of use
Sum/Rank
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Critical parts of the body of the CG&S document. You need a written section with
Scoring for each of the following;
1. Description of the alternatives considered
2. Discussion of the decision criteria; why were they chosen? why they are important?
These should come directly from the customer needs/FSD.
3. The thought process that resulted in the weighting factors. This should be heavily
driven by the FSD prioritized needs. Include the values.
4. An analysis of the process of scoring. Why did you choose the various scores?
Include the scores!
5. Review your results.
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