Chapter 02: Design Thinking Process

What is Design Thinking?

Design thinking is a human-centered, iterative problem-solving methodology that industrial designers use to create innovative solutions. It's both a mindset and a structured process.

Core Principles:

1. Empathy first: deeply understand users
2. Embrace ambiguity: don't rush to solutions
3. Iterate rapidly: fail fast, learn faster
4. Bias toward action: make to think
5. Collaborate: diverse perspectives create better solutions

The Double Diamond

The most common framework for visualizing the design process:

    DISCOVER  →  DEFINE  →  DEVELOP  →  DELIVER
    
    ◇               ◇           ◇           ◇
   /  \            / \         /  \         / \
  /    \          /   \       /    \       /   \
 /      \        /     \     /      \     /     \
--------→-------→-------→---→--------→---→-------→
Diverge  Converge  Diverge  Converge

Problem Space  →  →  →  →  Solution Space

First Diamond (Problem):

• Discover: Research broadly, gather insights
• Define: Narrow to specific problem statement

Second Diamond (Solution):

• Develop: Explore many solutions
• Deliver: Select and refine best solution

Phase 1: Discover (Research)

Goal

Understand the problem space, users, context, and constraints.

Activities

1. User Research Learn about people who will use the product.

Methods:

• Interviews: 1-on-1 conversations (30-60 min)
• Observation: Watch users in natural context
• Surveys: Quantitative data from many people
• Diary studies: Users document their experiences

Example Questions:

• "Walk me through how you currently do [task]..."
• "What frustrates you most about [product]?"
• "Tell me about the last time you [used product]..."
• "What would make your life easier?"

2. Market Research Understand competitive landscape and opportunities.

Activities:

• Competitor analysis (features, pricing, reviews)
• Trend research (emerging technologies, behaviors)
• Market sizing (TAM, SAM, SOM)
• Patent searches (avoid infringement, find inspiration)

3. Technical Research Understand what's technically feasible.

Investigate:

• Available materials
• Manufacturing processes
• Cost constraints
• Technical limitations
• Supplier capabilities

Research Deliverables

Persona: Fictional character representing user type.

NAME: Sarah Chen
AGE: 34
JOB: Marketing Manager
GOALS:
- Stay organized in busy schedule
- Balance work and family
- Reduce stress

FRUSTRATIONS:
- Too many apps and tools
- Forgetting important tasks
- Wasting time searching

QUOTE: "I need simple tools that just work."

Journey Map: User's experience over time.

Phase 2: Define (Problem Framing)

Goal

Synthesize research into a clear, actionable problem statement.

Activities

1. Insights Clustering Group research findings into themes.

Method:

1. Write each finding on a sticky note
2. Sort into groups by similarity
3. Name each group (theme)
4. Look for patterns and surprises

Example Themes:

• "Users struggle with setup"
• "Desire for personalization"
• "Trust in brand is critical"

2. Problem Statement Craft a clear, human-centered problem frame.

Template:

[User] needs to [need] because [insight].

Examples:

• ❌ "Design a better vacuum cleaner"

• ✅ "Busy parents need to clean quickly without heavy lifting because they have limited time and energy"

• ❌ "Make a smartwatch"

• ✅ "Fitness enthusiasts need to track progress without breaking focus because pulling out a phone disrupts their workout flow"

3. Design Criteria Define what success looks like.

Must Have (Requirements):

• Cost under $50 retail
• Weigh less than 2 lbs
• Work with one hand
• Comply with safety standards

Should Have (Goals):

• Intuitive without instructions
• Aesthetically beautiful
• Environmentally friendly
• Minimal maintenance

Could Have (Nice to Have):

• Customizable colors
• Smart features
• Modular accessories

Phase 3: Develop (Ideation & Prototyping)

Goal

Generate many possible solutions, then test and refine.

Ideation Techniques

1. Brainstorming Rules

• Quantity over quality (aim for 50-100 ideas)
• No criticism or judgment
• Build on others' ideas
• Wild ideas welcome
• Visual over verbal

2. Sketching Methods

Thumbnail Sketches: Tiny, fast sketches to capture concepts.

• 10-30 seconds each
• Fill entire page
• Focus on basic form

Concept Sketches: More detailed exploration.

• 5-10 minutes each
• Show key features
• Add annotations

Presentation Sketches: Refined visuals for communication.

• 30-60 minutes each
• Perspective, shading
• Context (hands, environment)

3. Ideation Prompts

SCAMPER Method:

• Substitute: What materials could you swap?
• Combine: What features could merge?
• Adapt: What could you borrow from other products?
• Modify: What could you change (size, shape, color)?
• Put to other use: What else could it do?
• Eliminate: What could you remove?
• Reverse: What if you inverted something?

Example (Coffee Mug):

• Substitute: Ceramic → Double-wall glass
• Combine: Mug + Coaster
• Adapt: Airplane cup holder grip
• Modify: Square instead of round
• Put to other use: Phone stand
• Eliminate: Handle (wrap-around grip)
• Reverse: Cool drinks instead of hot

What If...?

• What if it was 10x bigger/smaller?
• What if it cost 10x more/less?
• What if it was used in space?
• What if users were blind?
• What if it had no electricity?

Prototyping

Prototype Fidelity Levels:

Quick Prototyping Materials:

• Foam core (easy to cut, shape)
• Cardboard (free, accessible)
• Clay/plasticine (sculptable)
• Foam (lightweight, carveable)
• 3D printing (precise, fast)
• Wood (durable, finish-able)

When to Prototype:

• Early and often
• When words fail to convey idea
• Before committing to expensive decisions
• To test with users

Phase 4: Deliver (Refinement & Production)

Goal

Transform validated concept into manufacturable product.

Activities

1. Design Refinement Polish all details based on testing feedback.

Focus Areas:

• Exact dimensions and tolerances
• Material specifications
• Surface finishes (texture, color)
• Assembly method
• Packaging design

2. CAD Modeling Create precise 3D digital model.

Considerations:

• Design for Manufacturing (DFM)
• Draft angles for molding
• Wall thickness consistency
• Assembly method
• Tolerance stack-ups

3. Engineering Collaboration Work with engineers to ensure feasibility.

Key Discussions:

• Structural integrity
• Electronics integration
• Thermal management
• Safety and compliance
• Cost to manufacture

4. Design for Manufacturing (DFM)

Injection Molding Rules:

• Consistent wall thickness (2-4mm typical)
• Draft angles (1-3°) for part ejection
• Avoid undercuts (or plan for slides)
• Fillets at corners to reduce stress

3D Printing Considerations:

• Support structures needed?
• Layer orientation affects strength
• Wall thickness > 1mm
• Overhangs > 45° need support

5. Documentation

Technical Drawings:

• Orthographic views (top, front, side)
• Dimensions and tolerances
• Material callouts
• Surface finish specifications
• Assembly instructions

Bill of Materials (BOM):

Iteration: The Real Process

Reality of Design: The process is messy and non-linear. You'll jump between phases constantly.

Research → Define → Ideate
   ↑         ↓         ↓
   ←────←─ Prototype ─←
         ↓         ↑
       Test    ←─←─←

Typical Project Timeline:

Common Pitfalls

1. Falling in Love with First Idea

Problem: Stopping too early. Solution: Force yourself to generate 20+ concepts before choosing.

2. Skipping Research

Problem: Designing for yourself, not users. Solution: Talk to at least 5 target users before ideating.

3. Analysis Paralysis

Problem: Over-thinking, never building. Solution: Set time limits. Make quick, rough prototypes.

4. Ignoring Constraints

Problem: Beautiful design that can't be manufactured. Solution: Research manufacturing early, involve engineers.

5. Not Testing Enough

Problem: Assuming users will understand design. Solution: Test with users at every stage.

Design Thinking in Practice

Example: Redesigning a Desk Lamp

1. Discover (Week 1)

• Interview 8 people about their lighting needs
• Observe people working at desks
• Research competitor lamps

Key Insights:

• People adjust lamps 10+ times per day
• Glare on screens is frustrating
• Cluttered desks leave no space for base

2. Define (Week 2) Problem: "Desk workers need easily adjustable task lighting without sacrificing desk space because current lamps are bulky and awkward to position."

Criteria:

• Adjust position with one hand
• Minimal footprint (< 6" base)
• No glare on screens
• Cost < $100

3. Develop (Weeks 3-5)

• Sketch 40 concepts
• Select top 3 approaches: clamp-on, weighted arm, magnetic base
• Build cardboard prototypes
• Test with 5 users
• Winner: Weighted arm with touch dimming

4. Deliver (Weeks 6-8)

• CAD model in Fusion 360
• 3D print prototype
• Test durability
• Specify materials: aluminum arm, steel base, LED array
• Create technical drawings

Key Takeaways

1. Design thinking is iterative: expect to cycle through phases multiple times
2. Empathy drives innovation: understanding users deeply reveals opportunities
3. Diverge before converging: explore widely before narrowing
4. Prototype to think: making reveals insights that thinking cannot
5. Constraints fuel creativity: limitations force innovative solutions
6. Fail fast and cheap: test early with rough prototypes

Tools & Templates

Digital Tools

• Miro: virtual whiteboard for collaboration
• Figma: user flows and interfaces
• Notion: research documentation
• Airtable: BOM and project tracking

Physical Tools

• Sketchbook and pens
• Foam core and cutting mat
• Hot glue gun
• Calipers and ruler

What's Next

In Chapter 03: Sketching & Ideation, you'll learn specific techniques to rapidly visualize ideas and communicate concepts effectively.

Exercise: Pick a frustrating product you use daily.

1. Research: Interview 3 people who use similar products
2. Define: Write a problem statement
3. Develop: Sketch 10 alternative concepts (15 min)
4. Prototype: Build the most promising one with cardboard