Mechanical design, like most other sorts of design, starts with a recognition of a need or an opportunity which requires something (a “new device”) to be made in order to get the benefits that the situation requires or offers. The new device may be either stereotypical, ie a new version of a pre-existing entity, or a totally new concept – this is always the biggest divide in any form of design.
The stages of design are:
- defining the need or opportunity;
- developing a concept which will satisfy this;
- developing a physical system which will satisfy this;
- attending to all the zillions of details;
- prototype building, development and trials; and
- any re-design required to suit production.
Numerous factors need to be considered:
- market appeal, including appearance, sociological and ecological aspects;
- intellectual property rights of others, and protection for the in-house new device;
- the availability of materials of construction and manufacturing processes;
- the availability of adequate servicing;
- safety, especially in fault states or in the hands of inept operators;
- operator skills and training;
- what the competition is doing;
- delivery times; and, ultimately,
Unless all these things are adequately addressed at the design stage, it will all end in tears. Either:
- the new device will not achieve its performance targets, if in fact it works at all;
- the new device will itself fail, ie break, buckle, burst, etc;
- the new device will be too expensive to own and operate, and will lose market appeal, together with the corporate image of its makers;
- it will lead to lawsuits from accidents and/or intellectual property infringements;
- the maker company will go broke – remember the Leyland P76, a quite good car but not what the market wanted at the time.
All the above looks like pretty dry stuff and not really the stuff of cartoons, whereas from a designer’s point of view, design can actually be good fun and quite rewarding. The truth also is, though, that designers need to be almost infinitely far-sighted in relation to what can go wrong in the most bizarre situations. They are surrounded by lots of smart arses alecs, who have never had an original idea of their own, who are instantly ready to criticise anything which has been brought into existence by someone else or, with the benefit of hindsight, point out why a failure or accident should have been not only foreseen, but avoided at the design stage, as they hand one a Statement of Claim.
If one would like to see a lighter side of mechanical design, one could watch a few episodes of Top Gear, where the Mad Three try to develop or modify vehicles or put them to extreme or unintended uses. How they survive some of their escapades is a mystery.