Developing an Industrial Product, page 3:
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The design phase is based on the product concept which normally gives a list of desirable product attributes. It is discussed on another page.
The procedures of design will be quite different depending on who participate in the work: either only professional designers, or a workgroup which includes also customers or users of the product. These alternatives are not contradictory, in other words there are many possible combinations of them.
A professional designer is accustomed to work on an abstract level and can discuss the various properties of the product, like its usability, safety, beauty etc. He can also make use of all available theories of design.
As a contrast, a typical user seldom thinks of detached properties of a product; instead he or she prefers to regard the product as a whole, holistically. Instead of a theory of design the user would like to discuss and evaluate exemplars, i.e. other similar products, or realistic prototypes. You have to bear in mind these preferences if you wish to incorporate users closely in the design procedure.
In the following discussion "professional design" means that the designer, or a team of them, prepare their proposals without daily contact to the customers. The communication between the parties is secured by regular meetings where the state of the project and the latest draft proposals are discussed. The designers prepare renewed outlines until the customers and other involved parties become satisfied with them.
A lot of research has been done on the work methods of designers. One study approach
has been an empirical one: scientists have investigated the factual work
methods of famous (or just typical) designers. On the other hand, researchers have
tried to discover the most efficient method of artistic design; however, a general
formula for it has not been found.
It seems that there are at least three main styles for the design of artifacts: the
methods of logical reasoning; those that rely on subconscious maturing
of the task; and finally iterative methods. Their principles as well as realization are quite different, but competent designers are usually capable of using any one of them, depending on circumstances.
1. Design methods which employ logical reasoning aim at finding just one, final and optimal solution on the basis of given targets and factual circumstances. This technique is possible only if the designer knows exactly all the targets and restrictions as well as their mutual relations, and if these are accepted by all parties involved (including the end users of the product).
Design by logical deduction is thus possible only when the design assignment has been clearly defined and entails not too many subjective differences of opinion. In those fields of industrial production where this type of task is usual, it is even possible that researchers develop standard patterns of deduction or calculation which the designers can use in most tasks for finding the optimal solutions (or at least adequate ones). Such is the case in many fields of engineering where the prevalent theory of design includes algorithms and formulas of deduction for the design of, for example, traffic network or bridge construction. They can often be carried out by a computer, which can accelerate the design a great deal, especially when computer aided design (CAD) is used.
The design process using logical deduction is sometimes called "rational planning process" and it consists ideally of the following operations:
The initial three phases of the process are often readily feasible with the usual methods of informative research, like questionnaire or interview, observation and methods engineering. The phases 4 and 5 should be normal conventional routines for a proficient designer. The weakest point in the model are the phases 6 and 7 where you should consider simultaneously a multitude of requirements from different parties: the evolving necessities of various groups of people, the environment, production technology and conjunctures. Their common evaluation is obviously possible only if the consequences of alternatives are exactly known and there are not too many personal differences in their evaluation. Such a lucky condition is not common in the design of artifacts, and consequently a 100 percent "rational process" is seldom seen even if many designers have set it as an ideal goal.
2. The method of subconscious maturing and innovation is common in the design of artistic works. Often the designer sets the rational procedure (see above) as an ideal goal but in the factual process its phases become integrated. The technique often resembles the following sequence which has also been adopted as the framework of the present www-page on product development:
Analysis and evaluation are examined elsewhere, so below we discuss just the methods of synthesis. In the design of artifacts it is only seldom possible to follow a conscious, logical process from targets to the final proposal; more common is that the designer first lets the problem mature in the subconscious for quite a time, and if all goes well, the solution eventually pops up. Such an event has been described by many professionals practising various arts, for example Mika Waltari (1980, p.398...400), writer of the best-seller "The Egyptian":
"This intensive experience is brief, sometimes a few seconds, sometimes minutes. ... In advance of it, I had already devised many outlines for the future book, but all of them had seemed pointless ... This veritable flash, the genuine innovation resembles a mystic occurrence and it does not last long. Afterwards you can consciously try to understand it and make it clear to yourself. Only thereafter you can start to collect new material from a novel point of view, and then follows the final concentration in writing which can take several years..."
As a psychological phenomenon this experience of a creative artist seems to resemble the event where a member of the public discovers the hidden structure in a work of art, cf. Beauty of Discovery.
Waltari emphasizes that the best arrangement comes from the subconscious, not by forthright planning on paper even in the case that the work will be based on a lot of collected written information:
"If I write down collected facts in a manner too definite, it becomes an impediment... It is better to let this collected intelligence submerge into the subconscious, and later when I really need these elements for my work, they will come back to conscious thinking as evident facts. If I should this way forget some details, I have concluded that those particulars were perhaps not really important after all. ... If I would try to write down longer passages [before their due time] their idea would die: the thought would stiffen prematurely so that I could no more exploit it." (ibid. p.406.)
Some creative artists believe that it would be detrimental to disturb or try to speed up the workings of the subconscious. The most ingenious ideas are the most elusive: they easily fade and disappear if the innovator too rashly formulates them in language or by drawing:
"In hunting for ideas man's skill at staging represents the hunter's craft. Creativity is a question of staging a problem with such a setting, that something begins to happen, appear, and move within it. Now a being is "becoming" there, something becomes more visible, more credible. But it is only loosely trapped; it can escape if one approaches it too soon."
"The seizing of an idea is a process which one doesn't seem to be able to influence consciously. Conscious cognition is too coarse an instrument." (Pietilä 1985 p. 26.)
We know very little of the working procedures of the subconscious. It seems that to beget an invention the brain needs, beside the logical basis for the problem solution, also stimulation which the inmost layers of the brain normally produce all the time. This stimulation is in no way related to the conscious problem and (because we do not know its structure) it appears to be random. On the basis of these two stimuli (logical and random) the brain then produces tentative solutions for the problem, until one of them eventually becomes accepted in the conscious evaluation and the artist starts developing it further.
Admitted that we do not know how innovations are born, it is nevertheless possible to stimulate innovation, at least in team work, which is the most common approach in business organizations. There are some special techniques such as:
3. Iterative methods rely on the process of gradual improvement. The designer makes first a tentative draft of the project, and then corrects its weaker aspects or components in piecemeal fashion until a "satisfying" arrangement is found. This method is also called "incremental" planning.
An early example of iterative design is the ancestral method of artesans where tradition played a cardinal role; it provided the standard pattern from which the new product could be developed by making just a number of small improvements. However, today so many changes to the traditional model are usually needed that the usefulness of tradition has diminished. It can sometimes be used as one of the starting points of the professional designer, to give inspiration and preliminary solutions to base the new design on.
"Seldom the idea for a building appears as if from nowhere. There is always some kind of a link between the preceding work and the new one. ... Usually a previous project has been the preliminary stage of a later one. Something in it becomes the central theme for a new work" (Pietilä 1985, p. 26.)
As a starting point for the iterative design method you will need a tentative proposal, the quality of which is not critical. You can create it with any method, for example with any of the methods listed above. Sometimes you can start at an earlier version of the product that is to be designed.
Once a preliminary design is at hand, you repeat the following procedure until an optimum is found:
The iterative method has some inherent weaknesses. While iteration
usually leads to a better solution, it may nevertheless fail to find the best
alternative of all.
An example of this is illustrated in the figure on the left: if the
iteration process is started at option A, it will eventually lead to alternative
C. This is, however, only a partial optimum: while it is certainly better
than the neighbours, it is far from the absolute optimum S, which is radically
different and could never have been found by iteration only. Obviously, if you consider only alternatives that do not differ much from the old one you never invent something radically new.
Another weakness of the iteration method is that it can only handle one feature of the object at a time. If you have several alternatives which diverge from each other in more than one respect, you will find it impossible to compare and rank order them with the iterative method. Iteration works well if your alternatives differ in just one respect or attribute of the object, otherwise it may lead in the wrong direction.
The iterative method is at its best in the later phases of design, when you have created at least one potential solution (using other methods) and you feel that it is not yet optimal. Remember, though, that too prolonged a polishing can spoil some of the freshness and vitality of the project.
For the techniques of evaluation which you will need in the procedure of iteration, see Evaluation in Product Development.
Normally the responsibility and authority over product development is strictly the affair of the management of the business. The customers or the future users of the products are not invited to take part in the procedure.
There are, nevertheless, some special cases where the responsibility of developing the proposals or evaluating them can be shared with the future users of the product. Authentic users are not always unequivocally known in the phase of design of the future product, but often a workable substitute can be found in a suitable sample, for example of volunteers or of "snowball".
For collective design, some special methods are used, three examples of which are given below.
1. Design through research, combining the roles of designer and researcher, means that before starting the design activity, the designer personally carries out a few operations of research. Combining these two roles has several advantages:
Design through research is, of course, possible even in conventional professional design, discussed above, with methods like a questionnaire, observation or methods engineering, but these methods do not easily allow the studied persons to express other opinions than those that the researcher already expects. This means that the customer or user of the product is not really participating in the design.
There are other research methods, better suited for deeper involvement of people. Some of them allow the participants to influence design and present ideas for products that are perhaps new and surprising to the designer as well. These methods include the innovation stimulating techniques discussed above, and particularly the methods of thematic interview and consulting-type observation. Moreover, there are methods especially for team work, like action research, including the "democratic dialogue" and the methods of discussing the conflicts involved in present products, or their latest direction of development. The method of analogy means contemplating other products that are similar in some respects, and trying to develop new ideas starting from the existing products.
Design through research can be organized as team work where users have the same right to vote as designers have. The difficulty is that designers are used to operate with theoretical concepts and imaginary products, while users prefer deliberating existing products and exemplars or successful earlier products. A remedy is to work with realistic prototypes as much as possible, or to use an older version of the product and "make believe" that it already has those new functions or properties that the future model will have. The presence of a simulated or mock-up model makes it possible to use some methods of innovative work, like:
In the above modes of work one or several members of the team are actors and the others are the audience. The process continues then as normal innovative general discussion. It goes without saying that especially in the early stages you should not let seemingly imperative practical requirements restrict the free play of thought.
The development team should, of course, ideally include people selected among the future users of the product, the target customers, but if it is impossible a sample of volunteers is often used. The result will be more or less biased, but you can perhaps correct it later when evaluating the design proposal, by using a renewed sample selected with a better method.
An excellent example of design through research is Sirkka-Liisa Keiski's project (1998) for developing a new type of fixed furniture for kitchens. She first interviewed and observed a group of old aged people in their home kitchens, then she constructed a mock-up kitchen and finally tested and improved it during a second interview session. A photo of the mock-up.
2. A temporary organization of users and professional designers. Another usual way of collective planning is based on regular meetings of the designers and the future users of the products. In the meetings, the approach of action research can often be applied, the essential point being collective learning.
Participatory design is often organized so that there is a "technical team" of professional designers (and possibly researchers) who continuously prepares alternative proposals to be discussed in weekly general meetings with the users. Typical phases in the project are:
It is the task of the technical team, beside preparing the proposals, also to provide a "design language" so that all the participants can define their expectations and later understand the proposals of the technical team.
On the scale of buildings a pioneer work was the concise book Toward a Scientific Architecture by Friedman (1975). The writer states that to assist collective design, the designer must, in advance, prepare a repertoire that shows the user all the possible alternatives he has. Moreover, the repertory must contain warnings pertinent to each choice, e.g. its benefits, inconveniences and costs. But it is not up to the designer to criticize the choices of the user any more than the waiter of a restaurant criticizes the dishes his client chooses.
Architectural "repertories" intended for laymen have been developed by Heikki Kukkonen (1984), see examples of it. More embryonic attempts to the same direction are nowadays the sales brochures of factories producing prefabricated houses. They are seldom based on profound research, so it is quite possible that none of the given alternatives satisfy.
Quite the contrary, A Pattern Language (1977) developed by Christopher Alexander et al. is based on research both with regard to practicality and to comfort. The "pattern language" consists of 253 design instructions although the writers cautiously state that they, too, are only an example: each single community of people has a pattern language of its own, and so does even each individual. On the other hand, many patterns are archetypal, or common to all human beings.
Every pattern of Alexander's follows the same formula, described on page x of the book. The first picture is always an archetype-like example and there is also a short list of other forms that it is related to. The list is followed by a caption that clarifies what this pattern is all about. After this, an account is given of the empirical knowledge about the pattern and the variations of its application. Examples of Alexander's patterns.
3. A design machine can be called a programmed apparatus that you can use for producing automatically a design for a new product. The customer expresses his or her wishes by pressing buttons of a menu, and the automaton then creates a design on the basis of the exemplars and rules of variation that a professional designer has programmed into the machine in advance. To this effect, Yona Friedman (1975 B) and Nicholas Negroponte have used TV, computers and design algorithms programmed into them. They use the name "architecture machine" for this computer. Their purpose thus is to develop a "design maker" (cf. coffee maker).
It can sometimes be possible also to transmit the finished design to the machines of manufacturing, thus creating a system of computer-aided manufacture (CAM).
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December 22, 2004. Original location:
http://www2.uiah.fi/projects/metodi
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