Prototyping Techniques

What is a prototype?

A physical or virtual model that mimics the final product to test and refine ideas, identify issues early, and gather user feedback.

What is a physical prototype used for?

Testing user interaction, usability, functionality, ergonomics, and identifying design issues early.

Advantages and disadvantages of a physical prototype?

Advantages: Easy to understand, real user interaction, identifies problems early, good for decision-making.
Disadvantages: Time-consuming, expensive, harder to modify.

What is a virtual prototype used for?

Visual presentations, virtual testing, feedback on internal structures, and rapid iteration.

Advantages and disadvantages of virtual prototypes?

Advantages: Fast, cheap iterations, remote collaboration, detailed internal views.
Disadvantages: Less realistic, simulations may be limited.

What is an aesthetic prototype?

A non-working prototype that replicates the appearance, materials, colour, and surface finish of the final product.

Advantages and disadvantages of aesthetic prototypes?

Advantages: Shows real appearance, useful for visual evaluation.
Disadvantages: Doesn’t function, expensive to achieve realistic finishes.

What is a functional prototype?

A prototype that focuses on testing movements, mechanisms, and working components of the product.

Advantages and disadvantages of functional prototypes?

Advantages: Demonstrates real functions, gives reliable specifications.
Disadvantages: Expensive, often lacks aesthetics.

What is a high-fidelity prototype?

A prototype that is very close to the final product in materials, finish, and function.

Advantages and disadvantages of high-fidelity prototypes?

Advantages: Accurate user experience, precise ergonomics.
Disadvantages: Slow and expensive to build.

What is a low-fidelity prototype?

A basic, simple prototype used for early concept exploration.

Advantages and disadvantages of low-fidelity prototypes?

Advantages: Cheap, fast, encourages experimentation.
Disadvantages: Not precise or realistic.

What is a scale prototype?

A full-size or reduced-size model used to study proportions, ergonomics, and overall form.

What is a performance prototype?

A prototype used to test how a product performs under real-world stresses or environmental conditions.

What is a material prototype?

A prototype used to test material suitability, texture, weight, and durability.

What is an instrumented prototype?

A prototype fitted with sensors or measurement systems to collect performance data.

Advantages and disadvantages of instrumented prototypes?

Advantages: Highly accurate performance data.
Disadvantages: Slow and expensive to build.

What is rapid prototyping?

Fast production of prototypes using technologies like 3D printing.

What is SLS and its adv/disadv?

Definition: Laser fuses powdered material layer by layer.
Advantages: Very complex shapes, no supports.
Disadvantages: High cost, rough finish.

What is SLA and its adv/disadv?

Definition: Laser cures liquid resin.
Advantages: Very accurate, smooth surfaces.
Disadvantages: Weak materials, post-processing required.

What is FDM and its adv/disadv?

Definition: Thermoplastic filament is melted and extruded.
Advantages: Cheap, many material options.
Disadvantages: Visible layer lines, lower precision.

Differences between 2D and 3D drawings?

2D: Simple, clear views, fast to produce.
3D: Shows full form but harder to draw by hand.

What are informal sketches used for?

Early ideation, fast exploration, divergent thinking.

Advantages and disadvantages of informal sketches?

Advantages: Fast, flexible, easy.
Disadvantages: Low precision, hard for others to interpret.

What is a perspective drawing?

A drawing that uses vanishing points to create realistic depth.

What is orthographic projection?

A series of 2D views (front, side, top) showing true dimensions for manufacturing.

What is an isometric drawing?

A 30° angled 3D drawing used to show form clearly.

What are assembly drawings?

Drawings showing how parts fit together (fitted or exploded).

What is included in a part drawing?

Dimensions, tolerances, and a Bill of Materials.

Why is annotation important?

It communicates design intent and explains thinking.

What is a solid CAD model?

A fully defined 3D model containing volume, mass, and internal geometry.

What is a surface model?

A visual model with no volume; good for aesthetics but cannot be manufactured.

What is bottom-up CAD modelling?

Designing parts individually, then assembling them.

What is top-down CAD modelling?

Starting with the overall assembly shape and deriving parts from it.

What is motion capture used for in DT?

Analyzing human movement for ergonomics and product interaction.

What is generative design?

AI-driven design technique that generates optimal shapes based on constraints.

What is haptic technology?

Technology that simulates touch/force feedback in virtual environments.

What is VR used for in prototyping?

Immersive testing, walkthroughs, and visualisation.

How is AR used in design?

Overlaying digital models onto real-world environments for evaluation.

What are digital humans?

Virtual human models used to test ergonomics and interactions.

Advantages and disadvantages of digital humans?

Advantages: Many body types, no physical prototypes needed, safe testing.
Disadvantages: Limited realism, relies on software accuracy.

What is FEA?

A simulation tool that analyses stress, strain, and deformation in virtual prototypes.

What does FEA output?

Colour maps, stress/strain values, displacement, and safety factors.