The rational model
The rational model was independently developed by Herbert A. Simon, an American scientist, and Gerhard Pahl and Wolfgang Beitz, two German engineering design theorists. It posits that:
- Designers attempt to optimize a design candidate for known constraints and objectives.
- The design process is plan-driven.
- The design process is understood in terms of a discrete sequence of stages.
The rational model is based on a rationalist philosophy and underlies the waterfall model, systems development life cycle, and much of the engineering design literature. According to the rationalist philosophy, design is informed by research and knowledge in a predictable and controlled manner.
Example sequence of stages
Typical stages consistent with the rational model include the following:
- Pre-production design
- Design brief or Parti pris – an early (often the beginning) statement of design goals
- Analysis – analysis of current design goals
- Research – investigating similar design solutions in the field or related topics
- Specification – specifying requirements of a design solution for a product (product design specification) or service.
- Problem solving – conceptualizing and documenting design solutions
- Presentation – presenting design solutions
- Design during production
- Development – continuation and improvement of a designed solution
- Testing – in situ testing of a designed solution
- Post-production design feedback for future designs
- Implementation – introducing the designed solution into the environment
- Evaluation and conclusion – summary of process and results, including constructive criticism and suggestions for future improvements
- Redesign – any or all stages in the design process repeated (with corrections made) at any time before, during, or after production.
Each stage has many associated best practices.
Design is all around you
What is your objective when starting a new product, business, or project?
What is your objective when starting a new product, business, or project? In fact, a design refers to the plan for achieving that objective. Color, shape, technology, and function each are means of realizing this objective. It is because people always play a central role in design that it has the power to bring progress to society. We consider good designs to be things that truly enrich people’s lives or have the potential to do so.
Changing definitions of design
The meanings of words change gradually with the times. The word “design” is no exception. It’s said that the word first came into widespread use at the start of the 20th century. Over roughly 100 years since then, the meaning of the word has changed gradually. Another characteristic of the word “design” is the fact that it has different meanings to different people.
For these reasons, the Japan Institute of Design Promotion (JDP), an organization intended to promote design in general and the organizer of the Good Design Award, felt the need to issue guidelines concerning our thinking about design. Accordingly, a brief description of our thinking about design is provided below.
Our thinking about design
It’s said that the word “design” comes from the Latin word designare. Designare is said to have meant to draw a plan. For this reason, it is thought that the word design initially was used in this sense of a plan on paper. In fact, the characters used to write the word for design in Chinese have this meaning.
In light of this historical background, one might think that anything planned on paper could be called design, but this would seem to leave out the most important subject of what is the essence, or the central feature, of contemporary design.
Just what is central to design? After years of working with design, it appeared to us that the answer was “people.” While we may refer to them as “users” or by the lofty term “society,” people always are a central concern when a designer plans something new. The designer asks him or herself the questions “What do people need? What should I design for them?” We consider this to be the core that is of utmost importance to the contemporary definition of design.
We consider design to consist of the series of processes of thinking constantly about people most of all, identifying objectives, and planning ways to achieve them. We believe that what is realized as a result of this process is one design solution.
Design of products and services
One topic that is brought up often these days about design concerns the design of products and services. Since we think of design as we defined it above, the Good Design Award accepts entries for both products and services. But sometimes we are asked if mixing the two does not lead to confusion. We’d like to take this opportunity to spell out our guidelines on this subject.
Products and services often are discussed in binary opposition to each other. This is true not only in design but in other areas as well. This reflects the binary opposition between tangibles and intangibles. But we believe that when talking about design it might be better to think of products and services in a slightly different way. In the case of design, we think that the difference between products and services is a difference of focus. A product is a means of achieving a service, and a service is an objective. We believe that this is the difference between products and services. For example, the Sony Walkman was a big hit around the world at one time. Viewed as a product, the Walkman was a portable music player, but beyond that one could discern the objective of being able to listen to music while walking around. That was the service. Providing the portable music player made it possible to achieve this service. This is how products and services are related.
So what do you think the designers designed in this case? We believe that they designed both a product and a service. Or more accurately, we could interpret this as a case of using a product as a means of designing a service. When considering this example in screening of the Good Design Award, we would look first at the appropriateness of the service and then at the appropriateness of the product in light of that service. In other words, we believe that instead of separating products and services in design we should continue to look constantly at both, without regard for their tangible or intangible status, because the product itself is a means to an end.

and how to work designs between different devices
ReplyDeleteSeveral years ago “responsive design” was a buzzword, nowadays it is a must, a norm. A huge percentage of traffic comes from mobile devices, and Google also takes into account mobile-friendliness in the process of ranking your website. The term “responsive” refers to responding to the user’s context and behavior by taking into account the different view ports sizes and devices.
DeleteFixed layout means that it does not change based on the screen size or viewport size. Except for specific cases (e.g. a special medical device or a kiosk that requires designing only for that exact screen size, or designing for an Apple watch — currently there are only a small amount of screen sizes), so except for these cases, it’s better to design a layout that dynamically changes based on the screen size.
A layout is fluid when the size of the elements inside the layout is defined by percentages, so if it proportionally changes based on the view port size. As you can image, using only this as a solution results in sub optimal experiences either on small or on large view-port sizes. Here is a demonstration for you: