2: Engineering Design Process

Question 1

What is Engineering Design?

Answer 1

Engineering design is the structured and systematic process through which engineering knowledge and skills are applied to solve REAL-WORLD, OPEN-ENDED

Question 2

What is the novice approach to design? what are the issues with this approach?

Answer 2

novice approach: not systematic and involves trial and error strategy

Result is rarely optimized, rarely the most efficient in terms of time, money, and resources

Question 3

What is conceptual design? why is it important?

Answer 3

Conceptual Design is an early step in the engineering design process.
- It is important as one mistake can make the project impossible or very expensive

Side Note: All help provided by CAD is at DETAILED DESIGN, not this stage (conceptual design looks over the problem more generally, multi-disciplinary, more robust/changing, etc.)

Question 4

What are some common features / important characteristics found in all engineering design processes?

Answer 4

Features:
- each model presents the design process as a sequence of stages/steps
- there is a preferred order in which we do things in design

Characteristics:
- A clear understanding of your design goal is critical
- model illustrates a iterative process

Question 5

What are the 5 (or 6/7) stages of our design process model?

Answer 5

0. Obtain a problem
1. Study and clarify the problem
2. generate potential solutions
3. identify the most promising solution
4. develop and test solutions
5. implement solutions

x. ITERATION (review and revise solutions)

Question 5

Elaborate on stage 1 of the design process

Answer 5

stage 1: study and clarify the problem
goal: create a precise definition of the problem by establishing:
- What are we trying to accomplish
- Who are we doing it for (needs/wants)
- Constraints?
- Needed information?

Answering these questions determine our design specifications

Question 5

Elaborate on stage 4 of the design process

Answer 5

stage 4: develop and test solution

The solution from stage 3 is further analyzed, refined, and studied,

prototyping, experimentation, simulations, and stakeholder consultation are all used to improve and finalize the design

ITERATION PLAYS A SIGNIFICANT ROLE!

Question 5

Elaborate on stage 2 of the design process

Answer 5

stage 2: generate potential solutions
- process of identifying and documenting as many potential solutions as possible

Question 5

Elaborate on stage 5 of the design process

Answer 5

stage 5: implement solution

this includes our final construction and delivery of our solution

documentation of the project is needed

real-world projects may have on-going work:
- operation
- maintenance
- upgrades
- recycling

Question 6

Elaborate on stage 3 of the design process

Answer 6

stage 3: identify the most promising solution

we reduce the solution space to a single solution through 3 main steps:
- screening
- ranking
- scoring

design specifications from stage 1 will be used to justify our decision

Question 6

Elaborate on stage x of the design process

Answer 6

iteration

iteration happens between any 2 stages in our design model

the design process is never achieved with a single pass through as new information, issues, and ideas come to light as we engage with the process!

Question 7

Why do we use the engineering design process?

Answer 7

Compared to the novice approach of engineering, THE FOLLOWING INCREASE:

• the quality of the final solution
• the chance of completing the project on time
• the change of completing the project on budget

Question 8

elaborate on costs associated with the design process: What 2 types of costs are considered?

Answer 8

actual costs:
- the money, effort, and resources we spend or consume in a project at any point

costs committed:
- the actual cost to date PLUS the anticipated future costs for decision we MADE

Question 9

if you were to graph the actual costs curve vs the costs committed curve, what would the graph look like?

Answer 9

The actual costs curve would be exponential:
- low at the start, jumps up exponentially at end

the committed costs curve would be logarithmic:
- jumps up quickly at start and levels out until the end

Question 10

After graphing the actual costs vs costs committed diagram, what are the main takeaways?

Answer 10

INFO:
- the early stages of the design process are cheaper than later stages
- it costs less to make changes early compared to later!
- the decisions we make early determine most of the spending that comes later

TAKEAWAYS:
- The costs committed curve tells us the cost to address a major mistake made at any given time BUT THAT GOES UNDETECTED UNTIL LATE IN THE PROJECT
- the difference between the costs committed and actual costs curve at any point represent future costs we still have some ability to change!

Question 11

What is a stakeholder?

Answer 11

stakeholder: an individual, group, or organization influenced by a project, or has influence on a project

Question 12

How we categorize and prioritize stakeholders?

Answer 12

We use the Stakeholder Salience Model

stakeholders are categorized into 3 dimensions:
- power (a stakeholder’s ability to influence a project)
- legitimacy (a stakeholder’s moral or legal right to have a say in the project)
- urgency (describes how time sensitive a stakeholder perceives their needs)

We rank each stakeholder based on the number of salience dimensions
1: stakeholder has one dimension
2: stakeholder has two dimensions
3: stakeholder has all dimensions

Notes:
- salience is often dynamic, with groups increasing or decreasing in salience as the project goes on
- being thorough in this step is critical to a successful project

Question 13

What can you do after utilizing the stakeholder salience model?

Answer 13

We can use the salience model to develop a stakeholder engagement plan

Ex/
A table with strategies and on the right, we choose whether to use the strategy or not based on how many salience dimensions each stakeholder has

Question 14

What is the project management institute (PMI)?

Answer 14

It is simply another model we can use to categorize and prioritize stakeholders.

y-axis: impact (ability to influence)
x-axis: interest in the project

divide into 4 groups based on above:
- manage closely (high impact, high interest)
- keep satisfied (high impact, low interest)
- keep informed (low impact, high interest)
- monitor (low impact, low interest)

Question 15

What are stakeholder needs? What are the three types?

Answer 15

needs: captures the wants and wishes of the stakeholders and the things that will increase/decrease stakeholder satisfaction

expressed needs: needs the stakeholders are aware of and freely share

latent needs: needs that would please stakeholders but they might not be aware of

threshold needs: needs stakeholders expect but might not think to mention

Question 16

What are requirements?

Answer 16

Requirements:
minimal threshold our design must achieve and the qualities or features it must have (or not have) in order to be considered acceptable by stakeholders

Question 17

What are evaluation criteria? What is stakeholders satisfaction?

Answer 17

Evaluation critera:
Attributes of importance to stakeholders that determine satisfaction

0%: corresponds to a solution that just barely meets a requirement

100%: corresponds to a solution where further improvement do not increase desirability of a solution

Question 18

How do we check evaluation criteria and their corresponding stakeholder satisfaction?

Answer 18

We choose an evaluation criteria and create a satisfaction plot

Ex/
y-axis: satisfaction %
x-axis: cost ($)

starts initially at 0-200$ where satisfaction stays at 100%
Could go down after than and hit 0% at, say, 400$

Question 19

What is validation and verification?

Answer 19

Validation and verification are ways to check our work at each step:

validation: asks “have we accurately translated stakeholder needs to target design specifications?”
- happens in stage 1, may happen later too

Verification: asks “does our chosen design solution meet all requirements and maximize stakeholders satisfaction?”
- happens in later stages once we have a solution

Question 20

What should we be focusing on / not focusing on in stage 2 of our design process?

Answer 20

• Focus on quantity, not quality
• don’t fixate or anchor on one single idea. variety is the key to success
• set aside the target design specifications from stage 1
• don’t discourage wild ideas
• don’t judge ideas (yet)

Question 21

What are 4 methods we can use to generate as many ideas as possible?

Answer 21

Brainstorming:
- write down ideas, draw, make sure everyone has a change to contribute

Gallery method:
- team members work individually to create ideas
- ideas are assembled and reviewed by team
- iterative process where new ideas can be generated or old ideas and be modified, combined, or improved

C-sketch:
- team members sketch for a set amount of time then pass sketches to their right
- add or subtract from the sketch you recieve
- no words or descriptions, just pictures

Inverse and Extreme:
- A round of concept generation focusing on solving the inverse, or opposite problem
- Try to think of the most extreme solutions for each design requirement

Question 22

Elaborate on screening:

Answer 22

• the process of removing ideas that can never work BASED ON REQUIREMENTS!
• iteration should be used to save screened ideas if possible

Question 23

elaborate on ranking:

Answer 23

• a strategy to reduce the number of ideas to score
• less time consuming than scoring & BASE ON EVALUATION CRITERIA!
• goal is to identify the ideas with the most potential to maximize stakeholders satisfaction
• any concept that is about to be eliminated should be reworked (if needed)
• the number of solutions to be advanced is a balance on resources available for scoring and the need to ensure the best idea is included

Question 24

What are the three main ranking systems we spoke about?

Answer 24

Methods include:
- individual voting: each person gets a limited number of votes to vote for their favorite ideas that passed screening

Pairwise Comparison:
- compare each idea against every other concept one by one
- 1 point for each winner, half points for ties

criterion-based ranking:
- evaluate each criteria for each concept
- give a +, -, or 0 depending on anticipated performance

Question 25

elaborate on Scoring:

Answer 25

• quantitative
• time consuming
• goal is to max stakeholder satisfaction

Main tool: Weight Design Matrix (WDM)
- write a list of criteria
- assign a weight to each criteria (depends on how important a criteria is to stakeholders)
- score each idea on each criteria
Multiply scores by weights and tally the results

Note: Also remember to conduct a sensitivity analysis and interpret results carefully. Satisfaction curves can be used to help score as well!

Question 26

When can a stage be bypassed in part 3 of our design process?

Answer 26

A stage can be bypassed in stage 3: identifying the most promising solution when…
- small number of concepts remaining after screening (no ranking)
- ranking generating a decisive leader (no scoring)

Additionally multiple ideas can be carried through stage 3 to stage 4: Develop/testing
(usually one safe idea and one ambitious idea