Iterative design
The iterative process in design
Testing
Testing and evaluateTo judge the quality and performance of a product. are not just a ‘tick box’ exercises at the end of manufacture. Testing and evaluation should be continually carried out and used to modify a designer’s ideas throughout the whole iterative design A cyclic design process of modelling and testing to achieve gradual improvements to the design. process.
It is important for a designer to test their prototypeThe first working model of a design used for testing, development and evaluation. against the design specification by conducting a variety of tests under realistic conditions to ensure that the product is fit for purpose.
| Specification statement | Ideas for testing |
| ‘The product should turn on in the dark, using an LDR to prevent a child being scared in the dark.’ | Does the LDR work? This can be tested in a dark room. At what light level should the light be activated? |
| ‘The product must fit underneath a standard-sized single bed to be stored when not in use.’ | Take the product to a home with a standard-sized single bed and see whether it fits underneath. Does it need to be folded? Is it easy to fold up for storage and unfold for use? |
| Specification statement | ‘The product should turn on in the dark, using an LDR to prevent a child being scared in the dark.’ |
|---|---|
| Ideas for testing | Does the LDR work? This can be tested in a dark room. At what light level should the light be activated? |
| Specification statement | ‘The product must fit underneath a standard-sized single bed to be stored when not in use.’ |
|---|---|
| Ideas for testing | Take the product to a home with a standard-sized single bed and see whether it fits underneath. Does it need to be folded? Is it easy to fold up for storage and unfold for use? |
Feedback may be asked from the clientIn business, a client is a person or organisation that wants a product manufactured, eg a retailer., target marketThe group of people a product is made for. and other experts in the market. Allowing these groups of people to physically test the product, by handling and using it, will help in gathering useful feedback.
Client feedback
A designer’s initial design may not be exactly what the client had imagined, so feedback is vital to help adapt and improve the product. The client will have a clear idea of what the users of the product, known as the target market group, are looking for and may be able to give the designer feedback about changes they want to be made.
The client may have a particular branding style or a range of existing products that the designer needs to think about or include. As the client is paying for the services of the designer, the client’s wishes should be considered at each stage of the process.
Target market feedback
A group of potential users of the product can be given a prototype to test. These user trials aim to get honest and critical opinions from a range of people.
Expert opinion
Professionals in industry can provide insightful and appropriate feedback. They could have experience of how to make improvements, or how a product can be cheaper or easier to make.
