Ellington Criteria and Constraints

Ellington Criteria and Constraints

The Engineering Design Process

• Involves defining and solving problems or meeting needs 

• Must identify features that a successful solution must have

• Steps aren't always followed in order

Identifying Needs

• Engineering solution begins with a need

• May come from individuals, groups, or society

• 
  

Ocean Acidification

The acidity of our ocean water has increased by 30% since the beginning of our industrial expansion. The increase in acidity is due to the increase of carbon dioxide in our atmosphere from human activity. The increased carbon dioxide is absorbed into the upper layers of our oceans. Ocean acidification is a term for the process of the ocean absorbing the CO₂ , and it describes how the seawater composition is changing. 

Open Ended

What is NEEDED in this scenario?

Define Engineering Problems 

• Criteria = features or qualities the solution should have

• Constraints = limitations that engineers face during the design process

Examples of Criteria

• Who needs the solution

• What the solution should do

• Ways the solution may affect society

• How will success be measured?

Examples of Constraints

• Cost

• Time

• Resources

• 
  

Multiple Choice

An engineer is trying to design a phone case that can withstand a drop of 10 feet. Being able to withstand a drop of 10 feet would be a

• Criteria

• Constraint

Multiple Choice

An engineer is trying to design a phone case, but only has two months to do so. Having two months would be a

• Criteria

• Constraint

Multiple Choice

Which is a CONSTRAINT of the ocean acidification challenge?

• must increase biodiversity

• must decrease extinction

• can not cause harm to humans or organisms involved.

Open Ended

What do you think is the most important CRITERIA of the ocean acidification challenge?

Poll

How do you feel about identifying criteria and constraints?

• I am cool, I got this

• I get it, but I think I am going to make a few mistakes

• This is weird and difficult, they all seem the same

• What is even happening here?