Design, prototyping and construction (Chapter 11- Interaction Design Text)

Overview Prototyping and construction Conceptual design Physical design Generating prototypes

What is a prototype? In other design fields a prototype is a small-scale model: a miniature car a miniature building or town

What is a prototype in ID? In interaction design it can be (among other things): a series of screen sketches a storyboard, i.e. a cartoon-like series of scenes a Power Point slide show a video simulating the use of a system a lump of wood (e.g. PalmPilot) a cardboard mock-up a piece of software with limited functionality written in the target language or in another language A prototype is a limited representation of a design that allows users to interact with it and explore its suitability.

What else is a prototype? In software development, we prototype for other critical reasons: What are other reasons you might prototype on your project, besides for interaction ID? Member tracking software Blog and forum monitoring bot Tori’s project Multimendia database system Talk2Rosie Project management tool Network stress utility Etc. A prototype is a limited representation of a design that allows users to interact with it and explore its suitability. 5

Why prototype in ID? Evaluation and feedback are central to interaction design Stakeholders can see, hold, interact with a prototype more easily than a document or a drawing Team members can communicate effectively You can test out ideas for yourself It encourages reflection: very important aspect of design Prototypes answer questions, and support designers in choosing between alternatives They are very useful to help stakeholders understand what the development team is trying to achieve and can be used to communicate and avoid the “Yes But, Undiscovered Ruins and user developer syndromes” They can be used to clarify requirements, worry about technical feasibility of a product and evaluate to see if a particular design is compatible with the rest of the system.

What to prototype in ID? Technical issues Work flow, task design Screen layouts and information display Difficult, controversial, critical areas

Low-fidelity Prototyping Uses a medium which is unlike the final medium, e.g. paper, cardboard Is quick, cheap and easily changed Examples: sketches of screens, task sequences, etc ‘Post-it’ notes storyboards ‘Wizard-of-Oz’ Limited utility after requirements stage or for usability testing.

Storyboards Often used with scenarios, bringing more detail, and a chance to role play It is a series of sketches showing how a user might progress through a task using the device Used early in design

Sketching Sketching is important to low-fidelity prototyping Don’t be inhibited about drawing ability. Practice simple symbols

Exercise Draw a sketch of the “student feedback system” from any perspective in the room you’d like. Don’t look at what anyone else is doing. Compare notes with your team members. Any interesting insights based on how each person did this rough prototype?

Card-based prototypes Index cards (3 X 5 inches) Each card represents one screen or part of screen Often used in website development Card-based prototypes can be generated from use cases

‘Wizard-of-Oz’ prototyping The user thinks they are interacting with a computer, but a developer is responding to output rather than the system. Usually done early in design to understand users’ expectations What is ‘wrong’ with this approach? User It is difficult to achieve for large systems and the users might mistake the delay in response to a problem with the system and might end up focusing on performance rather than on the interaction model. Very often used to model speech recognition and text-to-speech systems. E.g., modeling user interaction with phone help menus before creating the real thing. This is also called PNAMBC prototyping (pronounced “penambic”), for “Pay No Attention to the Man Behind the Curtain.” >Blurb blurb >Do this >Why?

High-fidelity prototyping Uses materials that you would expect to be in the final product. Prototype looks more like the final system than a low- fidelity version. For a high-fidelity ID prototype in software, common environments include Macromedia Director, Visual Basic, and Smalltalk. Danger that users think they have a full system…….see compromises They might take too long to build, people might focus on superficial aspects(assuming that they are dealing with the actual system) rather than on content. A bug might spoil the whole process. Developers might have a desire to use this to develop the actual product(but the prototype may not have been designed with that in mind)

Compromises in prototyping All prototypes involve compromises For software-based prototyping maybe there is a slow response? sketchy icons? limited functionality? Two common types of compromise ‘horizontal’: provide a wide range of functions, but with little detail ‘vertical’: provide a lot of detail for only a few functions Compromises in prototypes mustn’t be ignored. Product needs engineering

Construction Taking the prototypes (or learning from them) and creating a whole Product must be engineered Evolutionary prototyping ‘Throw-away’ prototyping Most development groups tell the customer that the prototype is a throw-away What is the danger of using it as a starting point, anyway? Quality must be attended to: usability (of course), reliability, robustness, maintainability, integrity, portability, efficiency, etc Evolutionary prototyping involves evolving the prototype into the actual product. In “throw-away” the prototype is discarded and the development begins from scratch.

Conceptual design: from requirements to design Transform user requirements/needs into a conceptual model “an outline of what people can do and how to interact with it” Don’t move to a solution too quickly. Iterate, iterate, iterate Consider alternatives: prototyping helps What people can do – we can obtain them from the functional requirements The interaction model depends on a lot of things – who the users are, what kind of interface, what kind of interaction style should we use.

Guiding Principles Keep an open mind, but never forget the user Discuss ideas with all stakeholders Low fidelity prototyping Iterate, Iterate, Iterate Always keep the user in mind, it will be worthwhile to consider the user experience and if possible imagine or live it, the lump of wood(palm) that Jeff Hawkin carried around, the defibrillator that the book talks about.

Is there a suitable metaphor? Interface metaphors combine familiar knowledge with new knowledge in a way that will help the user understand the product. Three steps: understand functionality, identify potential problem areas, generate metaphors In CSSE 377 (Software Arch & Design 2), we’ll extend what you do here, matching mental models to metaphors and testing the results If you can appeal to something that the user is comfortable with, the interaction style will succeed. Think about the interface for child education videos, you can use the metaphor of a classroom or something that the kids enjoy.. Which one will you choose?

Evaluate metaphors How much structure does it provide? How much is relevant to the problem? Is it easy to represent? Will the audience understand it? How extensible is it?

Considering interaction types Which interaction type? How the user invokes actions Instructing, conversing, manipulating or exploring  See Ch 2, starting on p. 64 Do different interface types provide insight? WIMP, shareable, augmented reality, etc Instructing – Users issue instructions to the system Conversing – Users have a dialog with the system(conversation like ask Jeeves) Manipulate – By manipulating physical or virtual artifacts(like Wii) Explore – explore a virtual world(SIMS, 3d games)

Expanding the conceptual model What functions will the product perform? What will the product do and what will the human do (task allocation)? How are the functions related to each other? Sequential or parallel? Categorisations What information needs to be available? What data is required to perform the task? How is this data to be transformed by the system? Developing scenarios, essential use cases will help answer the functions that the system performs.

Reading Assignment Read Chapter 11 in the ID book 23

Summary Different kinds of ID prototyping are used for different purposes and at different stages Conceptual design (the first step of design) Consider interaction types and interface types to prompt creativity Prototypes answer questions, so prototype appropriately Construction: the final product must be engineered appropriately 24