1.7 Design as finding a good problem – solution pair
Design is an interesting form of problem-solving, since part of the problem is to find an accurate way of expressing what the problem is. This may sound paradoxical, but it is quite simple really. For example, if you commission an architect, you generally do not know what is possible within your budget. Some of your desires may be impossible dreams while some may be absolute necessities. Part of the architect's job is to help you, as a lay person, understand these things, explain what is possible, and to help you establish your priorities. Thus you might start the process by requesting a house with five en-suite bedrooms, a double garage, swimming pool and tennis court. For most of us, it would not take long to be convinced that the last two constraints make it impossible to find a solution within budget. So, they are removed from the specification, and the problem has changed. If however, you are a very keen tennis player you might be prepared to trade-off space in the house in order to build a tennis court in the garden. In this way you can consider the design process as partly looking for the problem (a specification that you can accept) to which a solution can be found. The design then reflects this problem–solution pair.
Which of the following design problems have a single, unique solution?
designing a house for a client
designing a ball gown for a princess
designing a bracket to support a shelf
designing a six-lane road bridge to cross the river Severn
designing a railway locomotive.
Which of the above involve finding a problem–solution pair?
None of them has a unique solution.
I will take each case in turn.
Designing a house for a client. This would involve finding a problem–solution pair – as discussed in Section 1.8. Specification of the 'problem' – the requirements of the client – will give some idea of the solution, but there will be a myriad of solutions in the end.
Designing a ball gown for a princess. This probably requires a problem–solution pair. The princess and dress designer would probably work up the design between them making many changes, until they were happy with the result. If the designer were working in isolation, the 'problem' would require greater specification: should the gown be low-cut, have a high hemline, etc.
Designing a bracket to support a shelf. In this case the requirement is essentially fixed and cannot be negotiated or changed. So no problem–solution pair. There might be different solutions, but only one problem.
Designing a six-lane road bridge to cross the river Severn. Again the requirement is fixed. There might be some negotiation about the form of the bridge, or even its position, in which case this might mean finding a problem–solution pair.
Designing a railway locomotive. This probably would involve some negotiation about the price and performance, and tests during manufacture might require modifications to the original specification. Also, problems encountered during the construction might requirement modifications to the specification.