4.9 Final implementation
The line you take here obviously depends on the problem you set out to solve. If you were creating a new product for retail or industry, then the final step of the process would be to put that product into manufacture and watch it go off into the world to begin its life cycle (Figure 20). If the solution were a one-off, such as the village water supply problem we considered at the start, then it would be built and installed.
Not all engineering problems will fall neatly into this pattern, inserting need at the top and extracting a solution at the bottom. Furthermore, not all problems and challenges are to do with designing something from scratch – many real challenges are concerned with a more restrictive need to improve or repair an existing system. Engineers work in different ways, under a variety of conditions and often without the luxury of the time, resources or finance it would take to follow the above process to the letter for every need that was presented. The process will vary according to the nature of the problem, and the experience and understanding of the team engaged to find the solution.
Explain why the list of criteria used in selecting the best candidate solution will look like the specification. State the reason for assigning weightings to each criterion.
The specification should be the document that defines everything that is wanted from the solution. Therefore this is the most natural basis from which to generate the list of selection criteria. A full specification will contain a large number of items, including some which are preferences rather than absolute, hard-and-fast necessities. If no weighting is applied, then the ranking of the candidate solutions could be incorrect in relation to the real need, simply because the best solution has a lower score on several relatively unimportant criteria.
In the next two sections I want to show some aspects of the problem-solving process at work.