Product Design and Development: Technical Principles

Requirements for Product Design

Learning Outcomes

  • Understanding the design, development, and manufacture of products to meet specification criteria and fitness for purpose.
  • Understanding how critical assessment leads to new designs.
  • Critically assessing products and developing new design proposals.
  • Working with various materials to produce creative and original products that satisfy the target market.
  • Developing inclusive product designs.
  • Ensuring accuracy of production.
  • Considering aesthetics, ergonomics, and anthropometrics in product design.

Introduction to Product Development and Improvement

  • Good design is often confused with aesthetics; however, practicality is crucial.
  • Products that look attractive but are impractical may not sell well.
  • Examples: Philip Starck's Hot Berta kettle and Juicy Salif lemon squeezer.

Product Design Specification (PDS)

  • A set of criteria to follow when designing a product.
  • Products are assessed against the PDS to evaluate their success and determine if they represent 'good design'.
  • Consider Dieter Ram’s 10 principles of good design.

Specification Criteria

  • The PDS requires clear, testable criteria based on investigation and research.
  • Stuart Pugh’s ‘total design’ emphasizes the importance of the PDS.

Common Elements in a Product Design Specification

  • Environment: Consider the product's impact on the environment (6 R’s - Reduce, Reuse, Recycle, Rethink, Refuse, Repair).
  • Testing: How the product will be tested.
  • Safety: All relevant safety standards.
  • Product Life Span: How long the product should last (durability).
  • Materials: Key material properties and manufacturing considerations.
  • Ergonomics: How the product interacts with users.
  • Aesthetics: Form, shape, proportion, etc.
  • Performance: How well the design functions.
  • Product Cost: Cost of materials, labor, and manufacturing.
  • Time Scale: Project deadline.
  • Size and Weight: Restrictions on size and weight.
  • Maintenance: How the product will be maintained/repaired.

Critical Assessment of Design

  • Design is constantly evolving; David Pye describes it as an "improvisation, a lash-up, something inept and provisional."
  • Design is transitory and evolves to meet current needs.
  • Critically assessing current and historical products guides the development of future products.
  • Society and consumer needs change over time.

Critical Analysis of Designs

  • Analyze your own design work and existing commercial designs.
  • Use the same criteria as the Product Design Specification (PDS) for product analysis.

User Centred Design (UCD)

  • Focuses on the end user at all stages of the design process.
  • Contrasts with mass-produced items based on generic research.
  • The user is part of the research, consulted on design concepts, and involved in initial testing.
  • The product should perfectly fit user needs.
  • A designer’s perception of a problem may differ from the user's.
  • Empathetic design: Designers experience the situation or problem themselves.

Concept Modelling

  • Used in early stages of ideation to assess development potential.
  • Can be quick models or more detailed and functional.
  • Software like SketchUp is useful for quick model ideas.

Initial Concept Generation

  • 2D or 3D sketch modelling (CAD or physical materials) to get client feedback before investment.
  • Sketches can identify ideas with development potential.

Block Modelling

  • Used after sketch modelling as 'proof of concept' or to explore form/function.
  • Materials: Blockboard, Foam board, and Styrofoam.

Visual Appearance Models

  • Focus on the product's visual appearance.
  • Physical or virtual models demonstrate the final appearance.
  • Modern CAD software generates photorealistic renders.

Working Prototypes

  • Made before production to test functionality, ergonomics, and criteria for further development.

Non-Working Prototypes

  • Have the appearance of the finished product for aesthetic and ergonomic evaluation.
  • Do not necessarily function.
  • Examples: portable medical dock and extending bike rear rack.

Rapid Prototyping

  • Uses CNC machinery like 3D printers and laser cutters for fast prototyping.
  • Can go from concept to prototype in hours instead of weeks.

Accuracy in Production

  • Inaccurate products will fail commercially and may be dangerous.
  • Designs must be suitable for production.
  • Simple geometric forms increase ease of manufacture.
  • Accurate, fully dimensioned drawings are necessary for effective component combination.

Dimensional Accuracy and Tolerance

  • The level of accuracy must align with production facilities.
  • CAD drawings can have accuracy to 8 decimal places, but machinery may not replicate this.
  • CAM machinery can manufacture precisely, but a working tolerance is factored in.
  • Working tolerance: Acceptable deviation that allows the product to function.
  • Handmade wooden furniture has greater tolerance, while microchips require great accuracy.

Aesthetics

  • Products that make you feel good are easier to deal with and produce harmonious results (Donald Norman).
  • Aesthetic properties appeal to our senses, primarily sight.
  • How an object looks and feels affects emotional connection.
  • Design elicits an emotional response, influencing consumer purchases.
  • Consider how designs will appeal to the target market.

Aesthetic Properties

  • Shape and Form: Contribute to a product's appeal.
  • Symmetry: Common in product design, especially in modern industrial design (e.g., Apple products).
  • Asymmetry: Can make a product seem playful or quirky.
  • Proportion: How mass or form is distributed, creating a sense of weight or accentuating form.
  • Golden Ratio: Considered proportionally perfect and visually pleasing.
  • Anthropomorphism: Designs reflect the human body, creating an emotional connection.
  • Colour: Vital for aesthetics, especially for established brands.
  • Symbols: Instructive symbols are standardized to avoid language barriers.

Ergonomics

  • The study of how humans interact with their environment and objects.
  • Successful products are ergonomically designed.
  • Evaluate ergonomics by listing pros and cons to identify areas for improvement.

Anthropometrics

  • Derived from "Anthropology" (the study of humans) and "Metrics" (measurement).
  • The study of human data, including height, weight, and field of vision.
  • Provides data to design products ergonomically.

Percentiles in Anthropometric Data

  • Instead of "average," data is referred to by percentiles.
  • The 50th percentile is generally considered the average.
  • Designers aim to fit between the 5th and 95th percentiles for accessibility.

The Measure of Man and Woman: Human Factors

  • A book considering every aspect of human data.

Ergonomists

  • Professionals who ensure products are ergonomically sound.
  • They design:
    • Products: Computer mouse or chair.
    • Systems: Food production facilities to maximize productivity and reduce accidents.
    • Environments: Car or aircraft interiors for comfort and safety.

Influence of Ergonomics on Design

  • Critical for product success.
  • Factors:
    • Colour: Used in power switches and dashboards.
    • Lighting: Correct level for screens and environments.
    • Sound: Important in phones and navigation systems.

Comfort

  • Influenced by size, materials, shape, sound, light, and temperature.
  • Adjustability is key for individual optimization.

Effectiveness and Safety

  • Ergonomics ensures safe and productive use.
  • The working triangle in kitchen design reduces distance traveled.

Health

  • Bad ergonomics lead to bad posture and health issues like curvature of the spine and RSI.
  • Good ergonomics are essential for long-term use or important tasks.

Examples of Ergonomics

  • Bad Ergonomics: Examples of products that could be considered poorly designed from an ergonomics perspective.
  • Good Ergonomics: Examples of products that could be considered well-designed from an ergonomics perspective.
  • Game Controllers: Nintendo pioneers ergonomic game controllers.

Intentionally Bad Design

  • Katerina Kamprani designed a collection of deliberately inconvenient products.

Inclusive Design

  • Developing products for diverse groups (disabled/able-bodied, young/old).
  • Changes for disabled users can benefit able-bodied users.
  • Designers use techniques to experience disabilities.
  • Use data, observation, and work with disabled users (UCD).

Adapted Products

  • Products changed to meet the needs of disabled users.
  • Designers aim to make products as ambiguous as possible.

Designing for Other Groups

  • People in the 95th percentile need XXXL clothing and adjustable car features.
  • Products for specific groups (high chairs, motorcycle helmets).
  • Exclusivity based on physical appearance or wealth is questionable.

Designing for Children

  • Children are generally in the 5th percentile.
  • Designers consider their smaller sizes and abilities.

Designing for the Elderly

  • Adults fit into the 50th percentile.
  • Elderly have limited physical ability, requiring adapted products.

Summary

  • Anthropometrics: Study of human data.
  • Ergonomics: Study of humans in their environment.
  • Percentiles: Percentage of people in a category; 50th percentile is ‘average’.
  • Modern products are ergonomically designed.
  • ‘The Measure of Man and Woman’ for anthropometric data.
  • Inclusive design for large user groups.
  • Elderly have specific physical needs.
  • Products require a Product Design Specification (PDS).
  • Concept designs communicated via 2D/3D forms.
  • Visual models and virtual prototypes develop ideas before production.
  • Modelling techniques assess form/function.
  • Aesthetic properties appeal to the market.

Revision Notes

  • Understand considerations for product design and development.
  • Use a PDS and UCD.
  • Refer to aesthetic properties for customer appeal.
  • Understand basic anthropometric data.
  • Consider use by the 5th to 95th percentile and inclusivity.
  • Critically analyze products.