3 Needs and problems
The last section has established that engineering is about satisfying needs. In fact, with so many needs, it's a wonder that not everyone is an engineer! So, now that we have talked about both needs and problems, the logical progression is to examine the relationship between them.
Take the water example as being a fundamental need. We can state it thus:
This village needs a supply of clean water.
When given that statement, we have a natural tendency immediately to start looking for potential solutions – a trough for rainwater, purification for river water, a pump for underground water and so on. We will start asking questions to get a clearer definition of the need – What's the average rainfall? Is the village near a river? Do we know of any existing supplies? What physical resources are available? How much water is needed daily – is ten litres each enough? What do we mean by 'clean'? etc. Seamlessly, the need becomes a problem that requires a solution. The definition of requirements makes it precise.
The problem becomes how to transfer and purify sufficient water from a source, say a river, half a kilometre away.
With this amount of detail we have a problem definition, and all that's left is to find a solution …
SAQ 2
(a) State, in a few words, the need which prompted the development of the Baylis wind-up radio.
(b) Make a list of bullet points that identify the engineering requirements involved in meeting the need for communication, like the list at the end of Box 4 'Meeting the liquid challenge'.
Answer
(a) The need for reliable, affordable access to broadcast health information in remote areas.
(b) adequate radio reception equipment
adequate power provision (clockwork and solar)
adequate manufacture and assembly
shipping and distribution
robust business plan.