A decision matrix is a tool to help engineers/designers/anyone choose between multiple options based on specific criteria. Each criteria is weighted on perceived importance for the end user/customer, and each design is rated on how well they meet the criteria, and ranked on an aggregate score of all the weighted criteria. The highest scoring design might not win in every category, but overall outperforms the other designs.

Design A connects a hose to a water container at the base, with lines to measure water level. Water is pumped up the hose on an automatic basis, chosen by the customer.

An Analytic Hierarchy Process (AHP) is used to determine the relative “weight” of each criteria. The “weight” of each criteria is determined by comparing the value the customer places on each criteria.

After determining the weight, each design is rated on how well they meet that criteria, then multiplied by the weight, which helps determine the overall score.

Design C has the highest score (by 0.030 points!) according to the Decision Matrix. Despite not scoring the highest in every single category, Design C does overall meet customer’s needs the best. According to the weights determined by the AHP, the water level alert and durability of the design is more important to customers than the cost, which is what made Design C overall the highest scoring. If Design C ends up being even more costly than originally anticipated, it will score even worse on the “low cost” criteria, which would make Design B the highest scorer, due to how close the scores were. It is important to keep in mind that if I run into cost issues later, I should re-evaluate my decision matrix and perhaps choose a new design.