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Using communication techniques to present design ideas


1 - Freehand sketching

  • Freehand sketches are drawings that are created using no technical equipment such as T squares, set squares and rulers.
  • Allows to show ideas in 3D and/or 2D.


To make it more effective:

  • different media, i.e. using pencils, ball point pens, fine liners, marker pens or coloured pencils.
  • grid paper can be helpful in showing scale or added a human figure.
  • use of arrows is a good way to show movement in certain directions.

2 - Digital photography / media

  • Ideas are created by editing photos and media.
  • Can be as simple as tracing over the top of an existing photograph.
  • Often used in making billboard advertising for new films.

3 - Cut and paste techniques

  • Used by fashion designers to use existing photos/images to help and inspire their own designs.
  • Again can be achieved by using tracing paper over an existing photo.

4 - 3D models

  • To help the user visual the end product prototypes or 3D models are sometimes made.
  • can be full size or smaller scale
  • can be made from a variety of materials - paper, fabric, cardboard, stryofoam or HIPS.
  • can be made from small plastic building bricks
  • system modelling can use breadboards or stripboard
  • computer modelling to make 3D printed models and simulations.

5 - 3D drawing

Can be isometric, oblique, one point perspective or two-point perspective.

Oblique and isometric projections

Isometric projections141286_orig.png

Oblique projectionsoblique_projection.jpg

One point perspective drawing

  • Often used in interior design.
  • Construction lines point in the distance to a single point called the vanishing point.


Two point perspective drawing

  • Two-point perspective uses two vanishing points, connected by a horizontal line.
  • Two-point perspective is useful when developing ideas in 3D.

Orthographic and exploded views

  • Orthographic projection uses a 2D drawing of each side of an object.
  • Orthographic drawings usually consist of a front view, a side view and a plan view.
  • A drawing board and parallel motion or T-square is used to project one view from another.
  • Orthographic drawing may be done using first angle projection or third angle projection.

Exploded view



Assembly drawings

  • An assembly drawing shows how parts of a product fit together.
  • They are often used to show how to assemble parts of model kits and flat-pack furniture.
  • There are two types:
  • A fitted assembly drawing shows the parts put together, and can be drawn in 2D or 3D.
  • An exploded drawing shows the parts separated, but in the correct relationship for fitting together. Exploded views are usually drawn in 3D, as illustrated.


6 Systems and schematic diagrams

  • used mainly for electronic projects
  • shows the inputs, processes and outputs



  • maybe hand drawn or made using a computer package such as Circuit Wizard.
  • labelled to show component names and values.

7 Computer aided design and specialist drawing programs

Computer aided design or CAD can be used in a number of different ways such as:

  • CAD freehand sketching
  • 2D modelling
  • 3D modelling
  • System design
  • Often used to design items to be made using computer aided manufacture (CAM) - like a lasercutter or 3D printer.

8 Record and justify design ideas clearly - annotated sketches

  • Annotation can be used with all of the above techniques.
  • They help to explain the ideas without the need to speak to them directly.
  • The can vary depending on what stage of the design process they are being used.

Design justifications:

  • user and design requirements
  • pros and cons of each design
  • ergonomics
  • sustainability considerations

Manufacturing details:

  • materials and components
  • dimensions
  • manufacturing process and techniques
  • sources of energy e.g. batteries, main, solar, wind etc.

9 Summary

  • Decide on suitable design strategies for your design problem or scenario
  • Choose a range of suitable communication techniques for your design problem or scenario.

10 Exam questions

  • Explain one reason why annotations are important when a designer passes their concepts to a manufacturer.
  • Explain one benefit and one drawback of freehand sketching versus CAD modelling.
  • Name two different design strategies that designers sometimes use.
  • List five things that a designer might annotate on their designs.
  • Choose a suitable communication technique and sketch out a product that you might find in your design engineering workshop.
  • Consider the advantages and disadvantages of collaborative designing.
  • Discuss the potential differences in communication techniques for the following products: pop up children's book, interior of a wedding venue, clothing for a triathlon athlete and systems for an Amazon locker