Concept Selection Methods
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Transcript of Concept Selection Methods
Chapter 7: Concept Selection
TECH 313Product Design and
DevelopmentMonday, February 2nd 2009
Dr. Seaman
Chapter 7: ConceptSelection
Chapter Table of Contents1. Introduction2. Development Processes and Organizations3. Product Planning4. Identifying Customer Needs5. Product Specifications6. Concept Generation7. Concept Selection8. Concept Testing9. Product Architecture10. Industrial Design11. Design for Manufacturing12. Prototyping13. Product Development Economics 14. Managing Projects
Objectives of this Chapter:
After this lecture and associated activities, students should be able to:
Understand the need for a structured method to select a product conceptKnow the six steps to guide a team through a concept selection processBe able to create a decision matrix spreadsheet for your team’s project containing:
Selection criteriaConcepts related to your team’s project
Concept Selection Defined
“The process of evaluating concepts with respect to customer needs and other criteria, comparing relative strengths and weaknesses of concepts, and selecting one or more concepts for further investigation and testing, or development”
Concept Development Process
Perform Economic Analysis
Benchmark Competitive Products
Build and Test Models and Prototypes
IdentifyCustomer
Needs
EstablishTarget
Specifications
GenerateProduct
Concepts
SelectProduct
Concept(s)
Set Final
Specifications
PlanDownstreamDevelopment
MissionStatement Test
ProductConcept(s)
DevelopmentPlan
Chapter 5 Chapter 5Chapter 7
BOM
Various Methods for Choosing a Concept
External decisionProduct ChampionIntuitionMultivotingPros and ConsPrototype and TestDecision Matrices – YOUR TEAM!
Exhibit 7-5
Needs for using a Structured Method for Concept Selection
A “structured method” for concept selection:Helps to maintain “objectivity” throughout the concept phase of product developmentGuides the product development team through a critical, difficult and emotional process
Potential benefits for using aStructured Method
Likely to be a customer focused product (customer needs)Helps to create a more competitive product by benchmarking against competitorsBetter product-process coordination with respect to manufacturing criteriaHelps to reduce the amount of time to marketUsing objective criteria helps to facilitate better group decision-making (emotions out)Helps in the process of documenting the decision process
Medical Supply Company retains a
Product Design Firm
Opportunity Statement: Develop a “reusable syringe” with precise dosage control for outpatient use
Two Major Problems with Current Reusable Syringe
CostCurrent product model is made from stainless steel
AccuracyProblems with metering accurate dosage
Company wants to tailor the new product toward to the physical capabilities of the “elderly”
Accurate dosage
7 Needs for Client – End Users
Ease of handlingEase of useReadability of dose settingsDose metering accuracyDurabilityEase of manufacturePortability
Design Concepts = 7 sketches
Each of the 7 concept ideas:Nominally satisfies the customer needs
Lets look at the sketches!
Concept Selection ProcessPrepare the Matrix
CriteriaReference ConceptWeightings
Rate ConceptsScale (+ – 0) or (1–5)Compare to Reference Concept or Values
Rank ConceptsSum Weighted Scores
Combine and ImproveRemove Bad FeaturesCombine Good Qualities
Select Best ConceptMay Be More than OneBeware of Average Concepts
Reflect on the ProcessContinuous Improvement
Example: Concept ScreeningCONCEPT VARIANTS
SELECTIONCRITERIA A B C D E F G REF.
Ease of Handling 0 0 – 0 0 – – 0Ease of Use 0 – – 0 0 + 0 0Number Readability 0 0 + 0 + 0 + 0Dose Metering + + + + + 0 + 0Load Handling 0 0 0 0 0 + 0 0Manufacturing Ease + – – 0 0 – 0 0Portability + + – – 0 – – 0
PLUSES 3 2 2 1 2 2 2SAMES 4 3 1 5 5 2 3
MINUSES 0 2 4 1 0 3 2NET 3 0 –2 0 2 –1 0
RANK 1 3 7 5 2 6 4CONTINUE? Yes Yes No No Yes No Yes
Example: Concept ScoringConcepts
A DF E G+
Master Cylinder Lever Stop Swash Ring Dial Screw+
Selection Criteria Weight RatingWeighted
Score RatingWeighted
Score RatingWeighted
Score RatingWeighted
Score
Ease of Handling 5% 3 0.15 3 0.15 4 0.2 4 0.2
Ease of Use 15% 3 0.45 4 0.6 4 0.6 3 0.45
Readability of Settings 10% 2 0.2 3 0.3 5 0.5 5 0.5
Dose Metering Accuracy 25% 3 0.75 3 0.75 2 0.5 3 0.75
Durability 15% 2 0.3 5 0.75 4 0.6 3 0.45
Ease of Manufacture 20% 3 0.6 3 0.6 2 0.4 2 0.4
Portability 10% 3 0.3 3 0.3 3 0.3 3 0.3
Total Score
Rank
Continue? No Develop No No
(reference)
2.75
4
3.45
1
3.10
2
3.05
3
Remember…The goal of concept selection is not to:
Select the best concept.
The goal of concept selection is toDevelop the best concept.
“The process of evaluating concepts with respect to customer needs and other criteria, comparing relative strengths and weaknesses of concepts, and selecting one or more concepts for further investigation and testing, or development”
Group Work for the 3 Product Development Teams
Begin developing a Team Web SiteWhat should be on the front page?
Develop a “decision matrix” to rate concepts for each team
- similar to Exhibit 7-5 (MS Excel file)
Reminders for Next TimeQuiz #5 over Chapter 7 – Concept SelectionLab time for:
Updating of Mission StatementUpdating “decision matrix” to rate concepts for each teamDevelop a “draft” Bill of Materials (BOM) with Low & High Cost
- Estimates (create an MS Excel file -similar to Exhibit 5-10)
Create sketches and rough CAD model for each conceptTeam project web site updates