2. ISE554 Human Computer Interaction Design 2.2 User Interface Design

3. Sources of Information to Support Design Interaction Designers require sources of information to help develop and integrate a design Sources: Scientific knowledge (cognitive psychology, organisational models etc.) Established techniques(input/output via menus, forms, cursor control etc.) Experience (design models, similar systems, interfaces etc) But whilst knowledge, techniques and experience are invaluable they do not apply themselves to a particular problem Hence the need for: Guidelines: a valuable term which is over-used and often mis-used… Important to distinguish between the different forms that guidelines take.

4. 1. Definitions Differentiate between: 1. HCI/ Interaction Design Principles and Rules for the Design of an eLearning System 2. User Centred Design Principles and Methods for the Design and Development of a Product, Artefact or eLearning System

5. 2. Definitions What is Design? (see Preece p 352) “A creative activity- it involves bringing into being something new and useful that has not existed before.” (Jones, 1981) It refers to: 1) the process of developing a product, artefact or system.. 2) the models of the artefact developed during the process..

6. 3. Design Product: The Lotus Bike

7. 4. Creative Design: Process and Product Paper “Artefacts and the Designer’s Process: Implications for Computer Support to Design” -DateArtefactsDesign ProcessMethods -1979FIRST BIKESADOPT ADAPT IMPROVE LEARNING CONVENTIONS -1980FUNNY BIKESEXPLORATION BREAK RULES - -1982UNIVERSAL BIKEANALYSISFORMULATE PROBLEM -1985MONOCOQUE 1 EMERGENCE EVOLVE NEW CONCEPT -1986MONOCOQUE 2ANALOGYMODIFY CONCEPT -1988INTER BIKEREFINEMENTADD FEATURES - -1990MONOCOQUE3SYNTHESISCOMBINE FEATURES -1992OLYMPIC BIKECOMPLETIONAPPLY MEASURES -Figure 5 : Bicycle History Design Process and Knowledge Development -See http://www.lindacandy.org.uk for the full history in words and images

8. 5. System Centered Design What can be built easily on this platform? What can I create from the available tools? What do I as a programmer find interesting to work on? How can I ensure that the product /outcome matches the specification? Is the program efficient?

9. 6. User Centered System Design -1 The Design is based upon the user’s Capabilities and needs Context Work domain Specific tasks Golden rule of Interaction Design: “Know The User”

10. 7. User Centered System Design - 2... is based on understanding the domain of work or play in which people are engaged and in which they interact with computers, and programming computers to facilitate human action.... From Denning and Dargan, p111 in Winograd, Ed., Bringing Design to Software, Addison Wesley Denning and Dargan, 1996 Three assumptions The result of a good design is a satisfied customer The process of design is a collaboration between designers and customers. The design evolves and adapts to their changing concerns, and the process produces a specification as an important byproduct The customer and designer are in constant communication during the entire process

11. 8. User-Centred Design Methods To achieve this, designers need to: 1) understand user requirements in the context of domains, market.. 2) determine appropriate representations for exploring and communicating ideas with users and to one another… Methods vary according to size, complexity and context of the design situation 1) Trial and Error Approaches appropriate for simple designs, early exploratory concept generation, limitations: cannot handle complex projects involving large teams… 2. Structured Approaches appropriate for large scale engineering design work (aircraft, vehicles, computer systems) limitations: involving users more difficult and often given low priority, heavy focus on detail not concept design-lack of creativity..

12. Computer tool: single application or machine Computer Environment : networked repertoire of tools Person : single individual working alone Team : groups of people with different skills expertise working as a group with common goals Context: company or institutional framework with different constraints according to market or conditions Computer toolComputer Environment Team+Computer Environment Person Team Context ObjectActivityActors

13. Domain Model:Steering Column Connector R1 R2 S1 Generate Client Formulate Problem Design Team Analyse Evaluate Select Design Manager Computer tool/ designer Specify Feedback MULTIK MODEL : DOMAIN MODEL REQUIREMENTS LAYER Impose Constraint Repeat Actors and Activities R= Requirements