APSC 100 Midterm

Engineering Design

Engineering Design

PROCESS through which engineering knowledge and skills are applied to solve real-world , open-ended problems.

Novice Design Process

Trial and error.

Repetition of implementation and refinement.

Disadvantages of Novice Design Process

May find solution, but very costly(time, money, resources) and likely not best solution.

Engineering Design Process

Systematic approach that improves chances of success and finishing on time and on budget.

Stages of Engineering Design Process

1. Study and Clarify Problem

2. Generate Potential Solutions

3. Identify Most Promising Solution

4. Develop and Test Solution

5. Implement Solution

&ITERATION

Iteration

Occurs throughout design process. Revisitation and revision of previous work.

Trend of Spending for EDP

Cost increase for later stages of design process.

Costs Committed

Future costs determined by design decisions.

Trend of Costs Committed in EDP

Early stages of design process are inexpensive to perform, but but have a large impact on costs later on.

Stage 1

Study and clarify problem

Goal of Stage 1

Identify stakeholders and their associated needs

Stakeholder

Anyone influenced by the project or who can influence the project.

Needs

Stakeholder wants or expectations of what the final design should be or do.

Note: Some may be so obvious that they are not mentioned.

Needs for Different Stakeholders

Can vary, be contradictory, and overlap.

Stage 2

Generating potential solutions

Goal of Stage 2

Generating as many potential solutions as possible.

Trend of Solutions

Over Time

Increase in number and variety over time.

Solution Space

Collection of all ideas generated.

Fixation/Anchoring

Getting stuck and solely focused on one idea. Very bad and causes severe lack of variety.

Guidelines for Solution Generation

-As many unique ideas as possible.

-Quantity over quality

-Resist developing first or favorite idea.

-Do not evaluate ideas yet.

-Generate a VARIETY of ideas

C-Sketching

Sketches passed around each member of group. No writing or talking. Very rough. Everyone gets equal time and input to every idea. Prevents domination.

Prototype

Simple models or representations of a final design. Occurs throughout EDP

Examples of Prototypes

Sketch, computer drawing, 2D and 3D models.

Prototype Classification

Focused(only show certain aspects of product) vs Comprehensive

Virtual vs Physical

Prototype Trend in EDP

Cheap, simple, quick prototypes in beginning of design process and become more detailed and accurate prototypes later on.

Purpose of Prototypes

Reduce risk

Cost of Error over Time

Increases over time

Stage 3

Identifying most promising solution

Goal of Stage 3

Narrow down possible solutions and identify solution to be developed.

Requirements

Threshold values of design parameters for a solution to be considered acceptable.

Steps of Stage 3

1. Screening

2. Ranking

3. Scoring

Screening

Identification and elimination of solutions that do not meet the requirements. (Look to see if modifiable before discarding)

Evaluation Criteria

Measures that distinguish between levels of performance or stakeholder satisfaction.

Ranking

Based on combined impact of evaluation criteria we sort remaining solutions in terms of approximate highest to lowest performance. Quick and rough process.

Scoring

Process of quantifying relative performance. Before performing this, remaining ideas are analyzed and studied in detail.

4 Ranking Methods

Individual voting, ranked voting, pairwise comparison, criterion-based ranking.

Individual Voting

Each teammate casts predetermined number of votes.

Ranked Voting

Team members rank top X concepts and points awarded based on ranking.

Pairwise Comparison

Concepts compared to each of the others. One point per better and .5 per tie.

Criterion Based Ranking

Compared to average for each criterion and concepts with most better than averages advance.

Scales

Breadth at which problem is viewed.

What changes based on scale?

Stakeholders, aspects of problem, potential solutions.

What stays the same independent of scale?

The goal.

Purpose of Weighted Decision Matrix

Objective and systematic method to make and justify our decisions. Quantifies relative merit of ideas.

When is the WDM used?

Scoring.

How are the scores structured?

0/10 if design has minimally acceptable performance

10/10 cannot improve further satisfaction

Can be scored on linear scale, 0 or 10, or on a curve.

What determines the weightings?

Priorities of stakeholders

How to determine final score for a design?

Multiply each of individual scores by their weighting and add them together.

Changing Weightings

Final ranking may change based on the weighting of the criteria. Same ranking with different weightings indicates robust decision.

Sustainability

Meeting the needs of the present without compromising the needs of the future.

Dimensions of Sustainability

Environment, economy, and society.

Bearable

Environment and society

Viable

Environment and economy

Equitable

Economy and society

4 Principles of Sustainable Development

Avoid removing materials at a faster rate than replenished, avoid making and releasing substances at a rate faster than they naturally break down, avoid degrading ecosystems at a rate faster than they naturally regrow, move towards happiness, well-being, and meeting the needs of all people.

Key Components of a Presentation

Audience, purpose, context

Audience

Who you are presenting to. You need to nderstand what the audience knows, and what they do and don't need to know. Helps determine focus, complexity and jargon use. Know audience opinion and what they want out of the presentation.

Purpose

Why the presentation you are giving is important. 2 main types are inform and persuade

Context

What lead you to giving presentation, setting of the presentation, time, tools, space. HOW & WHEN you will deliver it.

Validation

Confirming the target design specifications correctly describe the stakeholder needs

Verification

Does the design meet the specification?
Did we build the solution right?