Welcome to Core Component 3: Modelling!

Hello future designers! This chapter, Modelling, is absolutely critical to the Design Technology course. Why? Because you cannot design and build a perfect solution without first testing and visualizing your ideas.

Modelling is about creating simplified representations of complex things. It allows designers to fail fast, learn cheaply, and communicate clearly before committing to expensive production.

Don't worry if this seems tricky at first—we'll break down the different types of models, understand what makes them realistic, and see how they are used in the real world, from planning skyscrapers to designing apps!

1. The Fundamentals of Modelling

What is a Model?

A model is a simplified or scaled representation of an object, system, or concept. It is used to test, analyse, predict, and communicate ideas.

The Core Purposes of Modelling

Designers use models primarily for three reasons. Think of the mnemonic E-C-P:

  • Evaluation: To test performance, safety, and functionality (e.g., testing aerodynamics in a wind tunnel).
  • Communication: To clearly show clients, stakeholders, or manufacturers what the final product will look like (e.g., a detailed CAD render).
  • Prediction: To anticipate how a product or system will behave under various conditions (e.g., simulating traffic flow in a new city plan).

Models vs. Prototypes: A Key Distinction

This is a common point of confusion for students, but it’s straightforward:

  • Model: A representation used to visualize or test *aspects* of an idea. It doesn't necessarily have to work exactly like the final product. (Example: A scaled-down plastic model of a new aeroplane.)
  • Prototype: A fully or semi-working version of the product, built specifically for testing the *functionality and interaction* of the final design. A prototype is a high-fidelity model used late in the design cycle. (Example: The first working version of a smartphone app, ready for beta testing.)

Quick Takeaway: Models are for visualizing and testing *ideas*. Prototypes are for testing the *final product concept* before mass production.

2. Types of Models

Models fall into two main categories: Physical and Graphical.

2.1 Physical Models

These are 3D representations you can hold, touch, and see in the real world. They are often categorized by what aspect of the design they emphasize:

A. Aesthetic Models (Looks)

Focuses on the appearance, ergonomics, and tactile feel of the product.

  • Purpose: To evaluate form, color, texture, and size.
  • Fidelity: Usually high visually, but non-functional.
  • Example: A beautiful, smooth clay model of a new sports car body.
B. Functional Models (Works)

Focuses on the moving parts, mechanisms, and functionality.

  • Purpose: To test how the product operates, how robust it is, and the effectiveness of internal components.
  • Fidelity: The functioning parts must be realistic, but the external aesthetics might be ignored (e.g., open framework showing wires).
  • Example: A 3D-printed gearbox assembly used to test gear ratios and wear.
C. Conceptual Models (Explains)

These are often 3D sketches or rough mock-ups used early in the design process to quickly explore potential solutions and communicate abstract ideas.

  • Purpose: Idea generation and quickly showing how different parts or systems might connect.
  • Fidelity: Usually very low (made from simple materials like cardboard, foam, or wire).
  • Analogy: Think of a conceptual model like the rough "doodle" that explains the basic structure of a house before any blueprints are drawn.

2.2 Graphical Models

These are 2D or 3D representations created using drawings, diagrams, or computer software.

  • Sketches: Fast, low-fidelity drawings used for rapid communication of initial concepts.
  • Orthographic Drawings: Precise 2D views (top, front, side) used for manufacturing specifications.
  • Exploded View Drawings: Used to show how parts fit together, essential for assembly instructions.
  • Computer-Aided Design (CAD): High-fidelity, extremely precise digital 3D models.
    • Did you know? CAD models allow for virtual testing, such as Finite Element Analysis (FEA), where designers can simulate stresses and thermal performance without building a physical object.

Quick Takeaway: Physical models are tangible; Graphical models are visual representations on paper or screen. Choose the type that best communicates your current objective.

3. The Importance of Fidelity

What is Fidelity?

Fidelity refers to the degree of exactness or realism in a model or simulation when compared to the real object, system, or environment. Simply put: how close is the model to the final thing?

Levels of Fidelity

We generally classify models by their fidelity level:

Low Fidelity:

  • Characteristics: Abstract, simple, non-interactive, cheap, and very fast to produce.
  • Use: Early brainstorming, testing core concepts (the "is this a good idea?" stage).
  • Example: A napkin sketch or a paper mock-up of an app interface.

Medium Fidelity:

  • Characteristics: More detailed, includes some proportional accuracy, may involve basic functionality.
  • Use: Refining concepts, basic usability testing, communicating general design features.
  • Example: A wireframe CAD model or a foam core scale building model.

High Fidelity:

  • Characteristics: Extremely detailed, precise materials/textures, often fully functional, expensive and time-consuming to create.
  • Use: Final presentation, usability testing, and validating manufacturing techniques (i.e., prototypes).
  • Example: A full-scale, painted, working model of a device made with the actual materials.
Common Mistake to Avoid!

Students often assume higher fidelity is always better. This is false! In the early stages of design, low fidelity is preferred because it encourages rapid iteration and stakeholders focus on the *concept* rather than small visual details. Using a high-fidelity model too early wastes time and makes people less willing to suggest major changes.

Memory Aid: Low fidelity = Low cost, High speed, Focus on *concept*. High fidelity = High cost, Low speed, Focus on *detail*.

4. Simulation and Role-Playing

In addition to building physical models, designers use techniques to imitate or predict real-world performance.

4.1 Computer Simulation

A simulation is the imitation of the operation of a real-world process or system over time.

  • Purpose: Simulations are vital for testing scenarios that would be dangerous, expensive, or impractical to test in reality.
  • Key Applications:
    • Safety: Crash testing cars (virtual testing saves millions compared to physical crashes).
    • Ergonomics: Simulating how a surgeon interacts with a new tool.
    • Environmental Impact: Predicting how a structure will perform during an earthquake or hurricane.
    • Systems Design: Modelling logistics and supply chain efficiency.
  • Example: A flight simulator provides a high-fidelity virtual environment for pilots to practice dangerous maneuvers safely.

4.2 Role-Playing

This is a simple, yet highly effective conceptual modelling technique where people take on roles or act out scenarios to test usability and empathy.

  • Purpose: To gain deep insights into human factors, user behaviour, and emotional responses to a product or service.
  • Example: A group of designers acts as a family trying to assemble a piece of flat-pack furniture to identify pain points in the instructions or assembly process.
Advantages of Simulation and Role-Playing
  • Cost Reduction: Significantly reduces the need for expensive physical testing.
  • Risk Mitigation: Allows testing of dangerous scenarios without real-world risk.
  • Rapid Feedback: Variables can be changed instantly to see the effect on the outcome.

Quick Takeaway: Simulations and role-playing model *systems and behaviour* rather than just physical objects, providing crucial data on performance and user interaction.