Design, prototyping and construction By Anupa Mogili Arun Muralidharan Agenda Prototyping and Construction Conceptual Design Physical Design Prototyping and Construction What is a prototype? Why prototype? Different kinds of prototyping low fidelity high fidelity Compromises in prototyping vertical (“deep”) horizontal (“shallow”) Construction What is a prototype? For users to effectively evaluate the design of an interactive product, designers must produce an interactive version of their ideas, this activity is called prototyping. In other design fields a prototype is a small-scale model: a miniature car a model of a building In interaction design it can be a series of screen sketches a PowerPoint slide show a video simulating the use of a system a lump of wood, e.g. hand-held computer a cardboard mock-up a piece of software with limited functionality Why prototype? Evaluation and feedback: allows stakeholders to interact with an envisioned product, to gain some experience of using it in realistic settings and to explore imagined uses Communication among team members: clarifies vague requirements Validation of design ideas: test out the technical feasibility of an idea Choosing between alternatives: provides multiple designs for the application What to prototype? Technical issues Work flow, task design Screen layouts and information display Difficult, controversial, critical areas Low-fidelity Prototyping Does not look very much like the final product Uses materials that are very different from the intended final version, such as paper and cardboard rather than electronic screens and metal, e.g. palm pilot Used during early stages of development Cheap and easy to modify so they support the exploration of alternative designs and ideas It is never intended to be integrated into the final system. They are for exploration only. Examples of Low-fidelity prototyping Storyboards Sketching Index cards ‘Wizard of Oz’ Storyboard Originally from film, used to get the idea of a scene Snapshots of the interface at particular points in the interaction Series of sketches shows how a user can perform a task using the device Often used with scenarios brings more detail to the written scenario offers stakeholders a chance to role play with the prototype, by stepping through the scenario Storyboard example 1 Storyboard example 2 Sketching Drawing skills are not critical symbols to indicate tasks, activities, objects flowcharts for time-related issues block diagrams for functional components Sketching example Index cards Small cards (3 X 5 inches) Each card represents one screen multiple screens can be shown easily on a table or the wall Thread or lines can indicate relationships between screens like sequence hyperlinks Often used in website development Index card example (screen 1) Screen 2(next index card) ‘Wizard-of-Oz’ prototyping Simulated interaction The user thinks they are interacting with a computer, but a developer is providing output rather than the system. User >Blurb blurb >Do this >Why? High-fidelity prototyping Choice of materials and methods similar or identical to the ones in the final product Looks more like the final system appearance, not functionality Common development environments Macromedia Director, Visual Basic, Smalltalk, Web development tools Misled user expectations users may think they have a full system Difference Low-fidelity prototype High-fidelity prototype Advantages/Disadvantages Prototype Advantages Disadvantages Low-fidelity prototype - low developmental cost - limited error checking - evaluate multiple navigational and flow design concepts limitations High-fidelity prototype - fully interactive - look and feel of final product - clearly defines navigational scheme - more expensive to develop - time consuming to build - developers are reluctant to change something they have crafted for hours Compromises in prototyping All prototypes involve compromises Compromises in low-fidelity prototypes: device doesn't actually work Compromises in high-fidelity prototypes: slow response sketchy icons limited functionality available 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 Construction Creation, manufacturing of the final system Development philosophy based on experiences and feedback gathered from the prototypes evolutionary prototyping: involves evolving a prototype into the final product. throw-away prototyping: used as a stepping stone towards final design. Prototype is thrown away and the final system is built from scratch. Quality Although prototypes have undergone extensive user evaluation the final product still has to be subjected to rigorous quality testing for the following: reliability, robustness, maintainability, integrity, portability, efficiency Design Objectives Identify critical interaction aspects of the product (Conceptual Design) Select the appropriate tools and methods to provide interactivity (Physical Design) Realize that design of products usually involves several intermediate stages Consider the importance of early feedback for interaction design (Prototypes and Scenarios) Definition: ‘Conceptual Design’ “A description of the proposed system in terms of a set of integrated ideas and concepts about what it should do, behave and look like, that will be understandable by the users in the manner intended.” Conceptual Design Transformation of user requirements/needs into a conceptual model Stepwise refinement iterate, iterate and then iterate some more Consideration of alternatives prototyping & scenarios Three perspectives for a conceptual model Interaction mode Metaphor Interaction paradigm Running Example: Shared Calendar – Used in a corporate environment for employees to maintain their schedule and organize meetings based on that Interaction Mode How the user invokes actions activities by the user and the system’s responses Activity-based instructing, conversing, manipulating and navigating, exploring and browsing Object-based structured around real-world objects Process-oriented support work processes (e.g. financial software) Product-oriented develop products that users create, modify and maintain (e.g. Microsoft Excel, Word) Three perspectives for a conceptual model Interaction mode Metaphor Interaction paradigm Metaphors Interface Metaphors partial mapping of the software to a real object combine familiar knowledge with new knowledge help the user understand the product Three-step process for choosing a good metaphor understand system functionality, identify potential problem or complicated/critical areas, generate metaphors Evaluation of a metaphor How much structure does it provide? requires a sound and familiar structure How relevant is it to the problem? reduce confusion and false expectations Is it easy to represent? visual and audio elements combined with words Will the audience understand it? How extensible is it? extra aspects that can be useful later on Three perspectives for a conceptual model Interaction mode Metaphor Interaction paradigm Interaction Paradigm Coherent collection of interaction methods Addresses environmental requirements Desktop paradigm WIMP interface (windows, icons, menus and pointers) Ubiquitous computing Pervasive computing Wearable computing Mobile devices Three perspectives for a conceptual model Interaction mode Metaphor Interaction paradigm Expanding the conceptual model Functionality task allocation What will the product do and what will the human do? Relationship of subtasks categorizations all actions related to one particular aspect temporal associations (sequential or parallel) e.g. CASE tools Information data required to perform the task transformation of data by the system Scenarios in Conceptual Design Express proposed or imagined situations Used throughout the design process in various ways scripts for user evaluation of prototypes concrete examples of tasks as a means of co-operation across professional boundaries (shared understanding of the system) sell ideas to users and potential customers ‘Plus’ and ‘Minus’ scenarios exploration of extreme cases Prototypes in Conceptual Design Evaluation of emerging ideas user feedback, feasibility choice of methods and materials Continuous prototyping low-fidelity prototypes early on high-fidelity prototypes later Evolutionary prototyping early prototypes are gradually enhanced and augmented appearance functionality Physical Design Concrete, detailed issues of designing the interface although inaccurate, the term is also used for software-based systems Pervasive physical/conceptual design Guidelines for physical design Nielsen’s heuristics Shneiderman’s eight golden rules Style guides: commercial/corporate purposes collection of design rules and principles decide ‘look and feel’ Physical design for Computer Interaction Different kinds of ‘widgets’ dialog boxes, toolbars, icons, menus, etc Emphasis Menu design Icon design Screen design Information display Menu Design Arrangement number of menus length order of items categorization visual division (colours, dividing lines) sub-menus, dialog boxes screen size, input method applicability of entries Grouping Structure Terminology Constraints Context Activity Menu Design Compare the menu systems used on a digital camera a cell phone a digital music player (e.g. iPod) Criteria Functionality number of functions, categories Usability frequency of use, importance, consequences Constraints space, input methods Physical Design - Emphasis Menu Design Icon Design Screen Design Information Display Icon design Good icon design is difficult has to be widely acceptable meaning must be readily perceivable distinguishable from each other Meaning of icons cultural and context sensitive Practical tips always draw on existing traditions or standards concrete objects or things are easier to represent than actions Physical Design - Emphasis Menu Design Icon Design Screen Design Information Display Screen design Splitting functions across screens moving around within and between screens how much interaction per screen serial or workbench style Individual screen design white space balance between information/interaction and clarity grouping of items separation with boxes, lines, colors Splitting Functions across Screens Task analysis as a starting point each screen should contain a single simple step user frustration too many simple screens Context all pertinent information must be made available at relevant times multiple screens open at once Individual Screen Design User attention directed to salient point e.g. via colour, motion, etc animation is very powerful but can be distracting Organization Grouping physical proximity, colour, shape, Structure connections between related items Trade-off sparse population vs. overcrowding Physical Design - Emphasis Menu Design Icon Design Screen Design Information Display Information display Context relevant information is available at all times in the most efficient format for the specific task Types of information imply different kinds of display alpha-numerical, chart, graphs Consistency paper display and screen data entry different screens with similar information (customisable) information content vs. presentation Physical Design - Emphasis Menu Design Icon Design Screen Design Information Display Summary Different kinds of prototyping is used for different purposes and at different stages Construction: Make sure the final product is engineered appropriately Conceptual design (the first step of design) Physical design: e.g. menus, icons, screen design, information display Prototypes and scenarios are used throughout design as well Thank You !