7.6 End note
To end on a lighter note I would like to touch on a famous design case study from the history of navigation. Clocks in the 1700s only worked accurately if their mechanisms were kept still on the mantelpiece. But clocks were needed to tell the time at sea for the determination of longitude. Valuable prizes were offered and eventually a satisfactory design was created by John Harrison.
The new design certainly met a need. But the design did not behave in new ways – it still counted the seconds mechanically. There were numerous innovations in the internal clock mechanism to achieve the accuracy that was required. The new design behaved just as a clock should behave but in new conditions. The matching of design and operating conditions was the key to successful design. The design of the marine chronometer allowed the mechanisms of the clock to work independently of the disturbances of a voyage at sea. Clever design of the clock mechanism decoupled the internal function from external context.
Design is complex and there are many ways to handle this complexity. Design problems are commonly broken down into stages of increasing detail and definition. There are many activities in the process of design, and these are used in different mixes and with different emphases according to context. The various ways that designers approach complex problems where there are no clear or even rational answers, under conditions of extreme uncertainty makes design an exciting area of study. Design lies at the heart of engineering practice – it makes things which are useful, beautiful and, perhaps more often than it should, unsatisfactory. But that is what happens when we engage with complexity – surprise and disappointment, success and failure.
From the examples and case studies described in this course pick out what you think are informative examples of:
Make sure that you have a good reason for each choice!
Plastic kettle – new technology (materials) in existing context.
Bridges (e.g. the Millennium bridge) where conditions of use or operating conditions are not known completely in advance, leading to failure.
Sony televisions – same technology and function but different look. Folding bicycle has style but this is very much a product of close attention to function.
Stretcher carrier has 'a particular closely defined' context producing a functional design. Elaborate context of soap powder packaging where design has numerous contexts of market, competition and different production requirements.
This concludes our look at the process of design. In the rest of the course we'll look at many of the constraints on engineering within which designers have to work, and you will see illustrations of many different products and applications. The examples will be used to illustrate particular engineering principles, but in all cases try to think of them in terms of the overall design: context, function, style and innovation.