1. Decision Matrix Introduction to Engineering Design
© 2012 Project Lead The Way, Inc.

2. Develop a Decision Matrix
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Develop a Decision Matrix
A decision matrix is used to compare design solutions against one another, using specific criteria that are often based on project requirements.
A decision matrix is used to compare design solutions against one another using specific criteria. Design problem constraints are identified by the customer in the workplace. For classroom purposes, the student teams will be provided the constraints and will be required to develop a decision matrix.
A decision matrix is a design tool that may be used multiple times throughout a design process.

3. Identifying Ideas or Alternatives
What material would be best for creating models of puzzle pieces?

4. Idea #1 Modeling Clay Reusable Readily available Requires forming
Sticky
Imprecise geometry

5. Idea #2 Caramel Cubes Cheap Readily available Pre-shaped Sticky
Imprecise geometry

6. Idea #3 Dice Expensive Reusable Require two-sided tape
Moderately stable
Precise geometry

7. Idea #4 Centimeter Cubes Cheap Reusable Interlocking Protrusions
Precise geometry

8. Idea #5 Foam Blocks Expensive Reusable Require two-sided tape
Fall apart easily
Imprecise geometry

9. Idea #6 Sugar Cubes Cheap Readily available Require glue
Have messy granules
Fairly uniform geometry

10. Identifying Criteria Cost Reusability Geometry Connections Cleanliness
Resilience
Testability

11. Other Criteria Function Product life span Development time Size
Material costs
Development costs
Manufacturing costs
Company standards
Manufacturing capabilities
Safety

12. Develop a Decision Matrix
A grading scale must be developed to assign values for each criteria category
Rank Scale
Question Scale

13. Ranking The Alternatives
Presentation Name
Course Name
Unit # – Lesson #.# – Lesson Name
Ranking The Alternatives 2 3 1 4 2 1 1 2 4 3 2 1 1 2 3 4 1 2 4 3 1 4 2 3 10 12 17 22 14
The items listed at the top of the matrix are the constraints for the design problem. These constraints are typically identified by the client; however, for this example they were self-generated.
The items listed on the left side of the matrix are the brainstorming solutions for the design problem. These are generated by student teams.
The Reusable and Self-Adhering columns are examples of constraints that utilize the Question Scale (bottom right).
All other constraints utilize the Rank Scale (bottom left) to identify the best solution to the design problem.
The column on the right side of the matrix is the Total of the rankings for all constraints per proposed design solution. The solution with the highest total is considered the best solution to the design problem. Design decisions should be based on analysis and logic, not personal opinion. For this example, the interlocking centimeter cubes are the best solution to the design problem.

14. Idea #4 Is Right Decision
Design decisions should be based on analysis and logic; not personal opinion
Decision matrix is a tool that may be used multiple times throughout a design process