Topic 1: Design process
This topic introduces the design cycle model—a fundamental concept underpinning the design process and central to a student’s understanding of design activities. Each element of the design cycle represents how designers progress through the design process to refine the design solution in increasing detail. The topic then moves on to focus on the strategies that designers use to arrive at solutions to problems, and the varied nature of the skills and knowledge they need to carry out their activities successfully. The skills identified in this topic should be reflected in the internal assessment (IA) and reinforced throughout the course.
1.1 The design cycle model and the design process
Describe how designers use design cycle models to represent the design process.
Design may be described in a variety of ways and degrees of complexity. Some design cycle models are simple and some are more complex. The design process usually consists of successive stages that can be arranged as a systematic cyclical process that eventually converges to produce a solution to a problem.
List the stages in the IB design cycle model (DCM).
The DCM comprises six stages, as follows:
• identifying or clarifying a need or opportunity
• analysing, researching and specifying requirements
• generating ideas and solutions
• developing the chosen solution
• realizing the chosen solution
• testing and evaluating the chosen solution.
IB design cycle model
Describe a design brief.
• The design brief is the formal starting point for a new design. It is a statement of the expectations of the design. The brief does not provide the design solution, but is a statement that sets out:
• the design goal (for example, a working prototype to be evaluated in terms of its feasibility for volume production)
• the target market for the product (for example, for children, disabled adults)
• the major constraints (for example, should comply with new legislation, have fewer working parts, be cheaper to manufacture) within which it must be achieved
• the criteria by which a good design proposal may be achieved (for example, increased value for money and/or cost-effectiveness for manufacturer).
Describe the identifying or clarifying a need or opportunity stage of the IB design cycle model.
The context of the problem is described and a concise brief stated. The design process can begin with a problem, an identified need, a market opportunity, a demand, a desire to add value to an existing product, or a response to opportunities presented by technological developments. The initial design problem is a loose collection of constraints, requirements and possibilities. From this, the designer has to make a coherent pattern. The design brief states the intended outcome and the major constraints within which it must be achieved.
Describe a design specification.
The design specification justifies the precise requirements of a design. The specification will include a full list of the criteria against which the specification can be evaluated.
Describe the analysing, researching and specifying requirements stage of the IB design cycle model.
Developing the specification from the brief is an evolving process beginning with an initial set of specifications and culminating in a final product design specification (PDS).
Describe the generating ideas and solutions stage of the IB design cycle model.
Divergent thinking is used to consider ways in which a problem may be solved. The starting point for the generation of ideas should be the design specification, and proposals should be evaluated against this specification, with evidence of relevant research used to rate the ideas in terms of their usefulness. A variety of approaches should be used, and different possibilities explored and analysed, before deciding on the most suitable solution.
Describe the developing the chosen solution stage of the IB design cycle model.
A final concept is developed taking into account the conflicting needs of the manufacturer and the user, and the requirement of the design as set out in the specifications. A complete proposal is developed based upon the research and the designer’s personal ideas. This stage involves detailed drawings (of a style relevant to the task).
Describe the testing and evaluating the chosen solution stage of the IB design cycle model.
The final outcome is tested and evaluated against the requirements set out in the specification. Recommendations for modifications to the design are made. A reiteration process should now begin.
Explain why the IB design cycle model is not linear and why it is iterative in practice, thus making it representative of design thought and action.
The model emphasizes that designing is not a linear process. Evaluation, for example, will take place at various stages of the process, not just at the end. Similarly, ideas for possible solutions are not only generated at the “generating ideas” stage; some good ideas may develop even as early as the “identifying needs” stage. In practice, it is impossible to separate the stages of the design process as clearly as the model suggests.
Explain the role of the designer in the design process.
The designer’s role varies depending on the complexity of the process and the intended outcome.
Describe how designers interact with others and how the emphasis of the design process varies depending on the designer’s role.
Designers often work as members of a team. Priorities will vary depending on the nature of the activity. For example, the information required by an architect will be different from that required by an engineer.
Explain why elements of the model may differ in importance according to the particular design context.
Depending upon the nature of the problem, not all elements of the cycle carry the same weight in terms of time allocation and complexity. Points to consider include cost, resources, skills, time, original design specification and product modification.
Define incremental design, radical design, convergent thinking and divergent thinking.
Describe the relationship between incremental design and convergent thinking.
Describe the relationship between radical design and divergent thinking.
Explain how elements of the design model reflect convergent and divergent thinking.
Convergent thinking is analytical and solution-focused, for example, during evaluation. Divergent thinking is conceptual and problem-focused, for example, used to generate ideas.
Explain how design work is often a combination of incremental and radical thinking.
For example, the use of a new material for a product may be a radical leap forwards but the product may look very similar to previous products: a tennis racquet made from carbon fibre is a radical development, but the shape and form are similar to previous designs.
1.2 Generating ideas
Define constructive discontent.
Identify a design context where constructive discontent has been the primary generator of ideas.
Identify a design context where adaptation has been the primary generator of ideas.
Identify a design context where analogy has been the primary generator of ideas.
Identify a design context where brainstorming has been the primary generator of ideas.
Define attribute listing.
Identify a design context where attribute listing has been the primary generator of ideas.
Define morphological synthesis.
Identify a design context where morphological synthesis has been the primary generator of ideas.
Discuss why designers use a variety of techniques to develop ideas.
Actual techniques selected depend upon: personal choice, design context and time/resources available.
1.3 Communicating ideas
Define freehand drawing.
Describe the importance of annotating freehand drawings.
Annotations explain the thinking behind the visual image represented by the drawing. They allow the designer to consider the implications of the ideas for further development.
Explain the purpose of two- and three-dimensional (2D and 3D) freehand drawings.
Designers use a range of freehand drawings in the early stages of developing ideas to explore shape and form (3D) and constructional details (2D).
Define orthographic drawing.
Explain the purpose of an orthographic drawing.
An orthographic drawing shows details and dimensions and can be used as a production drawing.
Identify the stage of the design process where orthographic drawings are relevant.
Orthographic drawings are produced at the final solution stage and are used as working drawings in the realization stage.
Define isometric drawing.
Explain the purpose of an isometric drawing.
An isometric drawing depicts the proposed solution in 3D showing shape and form.
Define exploded isometric drawing.
Explain the purpose of an exploded isometric drawing.
The drawing is exploded to show component parts of a product and/or the sequence of assembly.
Define perspective drawing.
Explain the purpose of perspective drawing.
Compare perspective drawings with isometric drawings. Perspective drawings take into account spatial arrangements, for example, foreshortening, while isometric drawings are constructed to a set angle.
Define computer-aided design (CAD) and computer modelling.
Outline two advantages and two disadvantages of using CAD instead of traditional drawing methods.
Consider the skills required, storage, complexity and styles of the drawings, interfacing with other aspects of information and communication technology (ICT), time, cost and the purpose of the drawings.
Describe how an algorithm can be used to communicate a process.
For example, consider the operation of a lift. Correct sequencing is important, with input, process and feedback.
Define flow chart.
Draw a simple flow chart using symbols.
Describe how a flow chart can be used to communicate a process.
Explain the differences between flow charts and algorithms.
Describe models as representations of reality and representing selected features of a design.
Describe a range of physical models.
Consider scale model, clay model and prototype. Refer to a range of modelling materials, for example, clay, card, foam, board, balsa and wood.
Explain the purpose of the various models described in 1.3.22.
Define mathematical model.
Describe the role of spreadsheet software in the development of mathematical models.
Outline the advantages and disadvantages of graphical, physical and mathematical models.
Describe three advantages of using models as part of the design process.
Communication with clients, communication with team members, and ability to manipulate ideas better than with drawings.
Describe three limitations of the use of models in the design process.
Designers can easily make assumptions about how accurately a model represents reality: it may not work like the final product or be made of the same material.