Prototype 3 Prototype 2 Prototype

What is prototyping? Types of prototyping: – Evolutionary – Throw-away Good and Bad points to prototyping

For the most part, the system life cycle does allow new systems to be created which meet the needs of the user. However, the time it takes to create a system using the system lifecycle model can be considerably longer compared to some other methods (such as prototyping and RAD). Because of this problem, the system life cycle can sometimes produce a new system which no longer meets the needs of the customer.

Prototype designs often contain some elements of the final product. The first prototype might include some of the basic functions of the system: – Simple inputs – Some data processing – Some example outputs

A prototype might be completely different to the final product but it does allow end-users to test the system as it is being built and provide feedback. Prototyping allows the designer to confirm that they have interpreted the end-user’s requirements correctly as they go along. There can be many ways to describe the same thing which means that the interpretation of a description can also be different. Prototyping is popular because the designer and the end-user work more closely together when building a system thus allowing them to make sure they are making the same interpretations.

There are two methods of prototyping you need to be aware of: – Evolutionary – Throw-away

This is where one prototype is created and evaluated by the end-user. The second prototype is created based on the feedback from the first prototype. The prototypes keep evolving until a final product solution is agreed upon.

Early prototypes of parts of the system are created. The prototypes are then evaluated by the end user and the feedback received. The prototypes are then thrown away. This allows designers to quickly get feedback from end-users to make sure they have the right interpretation of the user requirements. Making changes early on in a project is more cost effective as less time is wasted in the long run.

Reduced time and costs – If changes are made early on in the project less time is wasted created a more developed product and then having to change it and develop it back up again.

Improved and increased user involvement – If end-users are involved in the design and creation stages of a project the designers end up knowing exactly what the end-user wants out of the system. – This avoids possible confusion later on in the project and also helps the designer create the product. – Also, being in contact with the customer/end-users allows the project to run more smoothly and hopefully on time.

Confusion between prototypes and end products – End users might think that a project is running ahead of schedule when they are shown a prototype. A prototype can be created in a day but coding all the functions could take weeks/months! – End-users might also like features in a prototype which were actually used for evaluative purposes. When they are thrown away they might think they are getting less of a product!

Excessive development time of the prototype – Designers sometimes run the risk of adding too much to a prototype. Prototyping is meant to be fast but sometimes a designer might spend too much time in the prototype stage perfecting little bits here and there. This increases costs and development time. – If a requirements are very clear then prototyping may not be necessary. Likewise, if the product is a standard design then prototyping may also not be necessary.