Week 9 Design and Prototyping

What is Prototype???
a mock up? experiment???full of bugs?
A prototype is a limited representation of a design that allows users to interact it.
It is paper-based outline of a screen/sets of screens, electronic "picture", 3 dimensional paper/cardboard mockup, stack of hyperlinked screen shots. It allows the stakeholders (clients and user) to do experiment, interact with an envisioned product, gain experience in realistic setting, explore imagines uses.
A prototype aid when discussing ideas with stakeholders, it act as a communication device among team members and it is a very effective ways to test the ideas. For examples, Clarify vague requirements,To do user testing and evaluation,Check a certain design.

Type of prototype:

• Low-fidelity
• High-fidelity

Low-fidelity

• does not look like final product
• tend to be simple, cheap and quick to produce for support the exploration of alternative designs and ideas.
• important during conceptual design and are never intended to be kept and intergrated into the final product. (for exploring only)

Type of low-fidelity :

• Storyboard: consist of a series of sketches showing how a user might progress through a task using the product under development.
• Sketching: relies on sketching but often people find it difficult to engage in this activity.
• Prototyping with index cards: use index cards (small pieces of the cardboard about 3x5 inches), each card represents 1 screen or one element of a task, in user evaluation, the user can step through the card.
• Wizard of oz

High-fidelity

• looks like final product
• common tools-0 flash, visual basic.....
• issues: Take too long to build, Reviewers and testers tend to comment on superficial aspects rather than content,Developers are reluctant to change something they have crafted for hours,A software prototype can set expectations to high, Just one bug in a high-fidelity prototype can bring the testing to halt.
• useful for selling ideas and for testing out technical issues.

Compromises in Prototyping

• by their very nature, prototypes involve compromises: the intention is to produce something quickly to test an aspect of the product.
• thus the prototype must be designed and built with the key issues in mind.
• there are 2 common compromises:
  
  • horizontal prototyping
  • vertical prototyping

Conceptual Design

• it concerned with transforming needs and requirements into a conceptual model( an outline of what people can do with a product and what concepts are needed to understand how to interact it)
• key guiding principles :
  
  • keep an open mind but never forget the users and their content
  • discuss idea with stakeholders
  • use low-fidelity prototyping to get rapid feedback

Developing an initial conceptual model

• some elements is a conceptual model with derived from the requirements for the product.
• some consideration to create initial conceptual model:
  
  • which interface metaphor would be suitable..?
• interface metaphors
  
  • combine familiar knowledge with new knowledge in a way that will help the user to understand the system.
• evaluating metaphor
  
  • how much structure does the metaphor provide?
  • how much metaphor is relevant to the problem?
  • is the interface metaphor easy to represent?
  • will you audience understand??

Interaction Type

• instructing
• conversing
• manipulating
• exploring