CONCEPT EVALUATION How to choose the best concept

CONCEPT EVALUATION How to choose the best concept? How to decide as a team? How to document the process?

CONCEPT EVALUATION How would a group come to consensus? Agreeing on a process Supporting the outcome of the process Merit-based debating Remaining cool and rational Emphasis is on discovery

METHODS OF DECISION-MAKING External decision Product champion Intuition Pros and cons Prototype and test Decision matrix

CONCEPT EVALUATION Possible methods of decision making External decision: Boss Product champion: A member Intuition: Gut feelings and vote

CONCEPT EVALUATION Pros & cons: Discussion & vote of majority. Prototype Decision and test matrix: Each concept is rated w/r to specifications and ranked.

CONCEPT EVALUATION IN ME 492 Two-stage Concept methodology screening Initial screening (when > 10 concepts) Concept screening matrix (> 5 concepts) Concept scoring matrix (< 5 concepts)

INITIAL SCREENING Multi-vote Group technique eliminates unlikely concepts. Allocate 10 dots to each members Choose the top 10 concepts

MATRIX METHODS Process 1. for using matrix methods Identify the criteria 2. Choose a datum 3. Rate the concepts 4. Rank the concepts

CONCEPT EVALUATION Concept screening matrix Evaluate concepts w/r to customer needs Use most important criteria Choose a reference (datum) concept A favorite design A competitive product

CONCEPT SCREENING MATRIX Compare each concept with the datum concept Give a score of + for “better than” datum Give a score of - for “worse than” datum Give a score of 0 for “same as” datum Rank concepts

CONCEPT SCREENING EXAMPLE PDS Criteria Datum Wall Clearance 0 0 0 1 0 -1 Bolt clearance 0 0 0 0 -1 -1 1 0 -2 1 -1 1 1 -1 -1 0 1 1 0 0 -1 -1 1 0 1 1 -1 3 -1 -1 0 0 -1 1 -3 Max Load Adaptability Effectiveness Weight Cost Total B C D E F

CONCEPT EVALUATION Combine and improve concepts Select promising concepts. Reflect on the process.

MATRIX METHODS It is important to have a single category for each important criteria. For example do not breakdown “cost” into: Cost Ease of manufacture / Assembly Material availability Labor This practice inflates some criteria

MATRIX METHODS If it is preferred to break down criteria, make sure the “importance” is also divided between them: Cost Or Materials Labor Tooling Importance 5 2 2 1 This method can be used in Scoring Matrix

CONCEPT SCORING MATRIX Concept scoring matrix The main criteria are listed as before Determine a weighting factor for each criteria Done Rating 1 in QFD (as importance) the concepts (1 -5): : Much worse than reference concept 2: Worse than reference concept 3: Same as reference concept 4: Better than reference concept 5: Much better than reference concept

CONCEPT SCORING MATRIX Alternate Rating 1 Absolute Scale Scoring the concepts (1 -5): : Useless – Very inferior 2: Poor - inferior 3: Acceptable 4: Good or superior 5: Excellent or much superior

EXAMPLE Consider buying a TV Selection Criteria Cost Screen size Image clarity Warrantee Looks

EXAMPLE Brand-A Cost: Brand-B Cost: $175, size: 19”, 6 month, 0. 19 mm, Beautiful Brand-C Cost: $350, size: 25”, 1 y, 0. 28 mm, OK looks $430, size: 27”, 2 y, 0. 28 mm, Very ugly Brand-D Cost $275, size 21”, 1 y, 0. 15 mm, ugly

CONVERSION OF CRITERIA

EVALUATIONS MATRIX

CONCEPT EVALUATION Rate and rank concepts Combine and improve Select one concept Consider variation in rates and weights on the final results. Assess how much difference is really significant. Reflect on the results This is “the point of no return” - Everyone on the team must be in agreement about it.

REFLECT ON THE RESULTS q Was your favorite option selected? If not, here are your options: 1. Ask for a second round of debating 2. Study the decision matrix, why did your design score lower than others? 3. Can you modify your design to address weaknesses 4. Did the team overlook strengths of your design?