structuring the search for the problemwhalen/course documents/geu 110/chapter three...

Structuring the Search for the Problem

• Problem Statement should focus on functions to be preformed

• Not be so specific as to Limit Possible Solutions– “Design a new lawnmower to be the best ever”

• Do Not Define problem in terms of Existing Products

• Focus instead on Function’s of Solution

Problem Formulation: MainTechniques

• Statement-Restatement Technique– By restating the problem; develop a better

understanding• Varying the Emphasis Placed on Certain

Words• Change Positives and Negatives• Substitute Explicit Definitions• Use Graphics or Mathematics

Present State - Desired StateDunker Diagrams

• Proper Problem Formulation by modifying the PS -DS until there is a match.

• Dunker Diagram– Three Levels of Solution

– General Solution• Some action required to match PS-DS

– Functional Solutions• Generated without consideration of feasibility

– Specific Solutions• Feasible solutions of the Functional Solutions

Kepner Treque Problem Analysis

• Problem Analysis – What is the problem (and what is it not)– Where did it occur (and when did it not)– When did it occur (and where did it not )– What is the Extent (number degree)

Structuring the Search for the Solution• Impossible to evaluate every solution path

– Need to eliminate paths that do not satisfy goals– Design task to provide most information possible in

problem solving effort– Use various attributes of the final solution state to

guide our choices in early decisions

• Subdivide Problem into Design Goals– Safety

• No Threats to User, Producers, Distributors

– Environmental Protection• Production thru Disposal

Structuring the Search for the Solution

– Public Acceptance• 70 – 80 % of all Commercial Products are Failures• Identify Potential Customers, Expectations

– Reliability• Product should Perform Every Time it is Used

– Durability• Resistance to Wear and Tear Performance

– Ease of Operation• Easy to Operate, Identify the Population

– Maintenance• Use Standard Parts, Avoid Expensive Tooling

– Cost• Challenge to Maintain Product Reliability, Durability

Structuring the Search for the Solution

• Design Specs or Quantitative boundaries – Physical

• Space, Weight, Energy Limits

– Functional• Operating Times, Vibrational Ranges

– Environmental• Moisture and Dust Limits, Temperature and Noise Limits

– Legal• Government Safety Codes, Environmental Constraints

– Economics• Production and Operating Cost, Depreciation