Human Computer Interaction Essays

Human Computer Interaction Essays Human Computer Interaction Essay Human Computer Interaction Essay The study of how people interact with computers and to what extent computers are or are not developed for successful interaction with human beings. What is HCI? â€Å"Human-computer interaction is a discipline concerned with the design, evaluation and implementation of interactive computing systems for human use and with the study of major phenomena surrounding them† (ACM SIGCHI definition of HCI). Creating usable systems (1) HCI investigates interaction between Human (1 user, a group, sequence of users) Computer (any computer big or small, process control, embedded, etc) used to perform various tasks in particular environments. Creating usable systems (2) The human factors †¦ different users different conceptions or mental models about their interactions different ways of learning, keeping knowledge and skills cultural and national differences user preferences change as they gradually master new interfaces Creating usable systems (3) The com puter factor †¦ different devices Smart phones, Touch Screen Kiosks, †¦ different capabilities and limitations Computing power, Input/output devices, †¦ different operating systems user interface technology is changing rapidly it offers new interaction possibilities to which previous research findings may not apply Visual, Tactile, Gesture based, †¦Also read about  Knowledge of PC boot processCreating usable systems (4) What about the interaction? Communication between user and computer Direct interaction Dialogue with feedback Control throughout performance of the task Indirect interaction Batch processing Intelligent sensors controlling the environment Creating usable systems (5) It aims to achieve 1. Usability (Useful, Usable, Used) 2. Safe 3. Effective 4. Efficient 5. Enjoyable system Creating usable systems (6) User compatibility Product compatibility `Task compatibility Work flow compatibility Consistency Familiarity Simplicity Control Creating usa ble systems (7)HCI focuses on user needs by assessing interface design amp; implementation according to usability criteria. ? Makes use of new, novel techniques amp; technologies. It applies usability design principles to achieve more productive amp; usable systems and more satisfied users. Creating usable systems (8) EC Directive 90/270/EEC Requires employers to ensure the following when designing, selecting, commissioning or modifying software: suitable for the task easy to use where appropriate, adaptable to user’s knowledge amp; experiences Creating usable systems (9) provides feedback on performance displays information in a format amp; at a pace that is adapted to the user It must conform to the principles of software ergonomics (Ergonomics is the science that deals with the interaction between people/work/environment/psychology.It considers the functions of the human body in the design of tools, equipment, etc. ) Designers amp; employers can no longer afford to ign ore the user!! Question †¦ Have you ever used a system that exhibit good HCI with the users? Give a few examples †¦ What systems have you used that exhibit bad HCI with the users? Name a few †¦ and why do you think they were bad? Historical basis of HCI (1) Second World War †¦ Study of interaction between humans amp; machines in order to produce more effective weapons (Bletchley Park, Enigma, Colossus) Ergonomic Research Society formed (1949) Research in Man-Machine Interaction began to spread Historical basis of HCI (2) Historical basis of HCI (3) Historical basis of HCI (4) Basic Interaction (1) Graphical Objects 1963 (MIT) Graphical Objects manipulated by a pointing device (light pen) Objects could be selected, moved, resized, etc. 1966 (Imperial College, London) Icons, Gesture Recognition, Dynamic Menus, etc. 1970 (XEROX PARC) Object selection and manipulation WYSIWYG Basic Interaction (2) Mouse 1965 (Stanford Research Lab [SRI]) Created to be a cheap re placement for light pens 1970 Adopted at Xerox PARC First appeared commercially as part of The Xerox Star (1981), The Apple Lisa (1982), The Apple Macintosh (1984). Basic Interaction (3) Windows 1968 (Stanford Research Lab [SRI]) 1969 1974 (Xerox PARC) Smalltalk System 1974 (MIT) EMACS Text Editor 1981 (Xerox PARC) The Cedar Window Manager 1981 Xerox Star 1982 Apple Lisa 1983 (Carnegie Mellon University funded by IBM)) Andrew window manager 1984 Apple Macintosh The early versions of the Star and Microsoft Windows were tiled, but eventually they supported overlapping windows like the Lisa and Macintosh. Applications (1)Drawing programs uses a mouse for graphics (1965) uses a tablet (1971) handling of lines and curves (1975) Text Editing first word processor with automatic word wrap, search amp; replace, user-definable macros, scrolling text, amp; commands to move, copy, and delete characters, words, or blocks of text (1962) screen editing amp; formatting of arbitrary-sized strin gs with a lightpen (1967) mouse-based editing (1968) first WYSIWYG editor-formatter (1974) Applications (2) Spreadsheets initial spreadsheet was VisiCalc (1977-8) for the Apple II HyperText the idea where documents are linked to related documents (1945) Ted Nelson coined the term hypertext (1965) NLS system was one of the first on-line journals, and it included full linking of articles (1970) HyperCard from Apple (1988) significantly helped to bring the idea to a wide audienceTim Berners-Lee used the hypertext idea to create the World Wide Web in 1990 at the government-funded European Particle Physics Laboratory (CERN) Mosaic, the first popular hypertext browser for the World-Wide Web Eg: Cosmic Book Applications (3) Computer Aided Design (CAD) first CAD systems similar to drawing programs (1963) pioneering work on interactive 3D CAD system (1963) first CAD/CAM (manufacture) system in industry was probably General Motors DAC-1 (about 1963) Video Games first graphical video game was probably SpaceWar (1962) the first computer joysticks (1962) early computer adventure game was created (1966) first popular commercial game was Pong (about 1976). Up ;amp; Coming Areas (1) Gesture Recognition first pen-based input device used light-pen gestures (1963) first trainable gesture recognizer (1964) a gesture-based text editor using proof-reading symbols (1969) gesture recognition has been used in commercial CAD systems since the 1970s came to universal notice with the Apple Newton (1992)Multi-Media multiple windows with integrated text and graphics (1968) Interactive Graphical Documents project was the first hypermedia system which used raster graphics and text (1979-1983) Diamond project explored combining multimedia (text, spreadsheets, graphics, speech) (1982) Up ;amp; Coming Areas (2) 3-D first system 3-D CAD system (1963) first interactive 3-D system used for molecular modelling (1966) the late 60s and early 70s saw the flowering of 3D raster graphics funded by the government the military-industrial flight simulation work of the 60s 70s led the way to making 3-D real-time Virtual Reality original work on VR funded by Air Force (1965-1968) study of force feedback, early research on head-mounted displays and on the DataGlove (1971) Up ;amp; Coming Areas (3) Computer Supported Cooperative Work remote participation of multiple people at various sites (1968)Electronic mail, still the most widespread multi-user software, was enabled by the ARPAnet (1969) and by the Ethernet from Xerox PARC (1973) an early computer conferencing system (1975) Natural language and speech Speech synthesis Speech recognition HCI as a business necessity Can the users be ignored? (Linux, Windows,†¦) NO HCI + Usability engineering are a crucial business necessity Good Interface ;amp; Interaction Design should not Be added after system is built Supporting users is an integral part of the design. To do this one must consider †¦ International Standards in HCI and Er gonomics User population is growing (size, diversity, etc. ) Expanding awareness amongst users of what can be achieved Case Study (1) A mechanical syringe was once being developed. An input device had to be created in order to enter the injected dose. Design such a device †¦ Case Study (2) A prototype was developed by the manufacturing company and demonstrated to the hospital staff.Happily they quickly noticed the potentially fatal flaw in its interface. Case Study (3) The doses were entered by a numeric keypad: an accidental keypress and the dose could be out by a factor of 10! The production version had individual increment/decrement buttons for each digit . Safety-critical systems (1) Poor designs Very common in Safety Life-critical Which all depend on computer-control We need to understand why Disasters Accidents Frustrations happen? Can you mention some examples? Safety-critical systems (2) Computer failure hits post office Lancashire,  UK   Sep 5, 2006 A VILLAGE post office has been struck by a technical glitch, leaving customers unable to pay bills and collect benefits. Edgworth 999 Ambulance Computer Failure Putting Lives at Risk International News Service,  Australia   Aug 23, 2006 LIVES are being put at risk because of a crisis with London Ambulance Services computer-controlled 999 system. US Department of Energy sponsors storage research CTR,  CA   20 hours ago The data storage institute will focus its efforts in three areas: collecting field data about computer failure rates and application behaviors, disseminating Temporary failure hits Houston 911 center abc13. com,  TX   Sep 8, 2006 system. This past July, the Houston Emergency Center experienced a computer failure which knocked out the automated dispatch system. Warning on need for super reserves The Australian,  Australia   Sep 10, 2006 must maintain 4 per cent of assets in liquid form to meet any immediate needs, rising from banking and operational risks, such as computer failure or staff Book on IT debacles urges caution Stuff. co. nz,  New Zealand   Aug 27, 2006 That is the central theme of Dangerous Enthusiasms – E-Government, Computer Failure and Information System Development, a 160-page book just published by Search is on for escaped McMinn inmates Chattanooga Times Free Press,   USA   Sep 8, 2006 A computer failure that left 225 inmates under supervision of just four corrections officers may have contributed to the 4:59 pm | Computers delay Charlotte flights Charlotte Observer,  NC   Sep 6, 2006 two dozen US Airways Express flights going in and out of Charlotte were canceled Wednesday after a thunderstorm in Ohio led to a computer failure that affected Homes facing night without water BBC News,  UK   Aug 20, 2006 and Powys. The Pant storage tank ran dry after the water firm was not alerted to the problem because of a computer failure. She Safety-critical systems (3)Air-traffic control Aircraft crash due to problems pilot had to interpret information on cockpit display Manned spacecraft On June 4, 1996, the maiden flight of the European Ariane 5 launcher crashed about 40 seconds after takeoff. Media reports indicated that the amount lost was half a billion dollars. The error came from a piece of the software that was not needed during the crash!! Safety-critical systems (4) Nuclear power plant (The Meltdown at Three Mile Island 1979) â€Å"As alarms rang and warning lights flashed, the operators did not realize that the plant was experiencing a loss-of-coolant accident. They took a series of actions that made conditions worse by simply reducing the flow of coolant through the core. Medical Institutions Break down in the scheduling system led to delays in reaching seriously ill patients. (UK) Disaster examples 1988 USS Vincennes shot down an Iran Air A300 Airbus with 290 people aboardAegis weapon system had Sophisticated software to identify potential threats BUT Was una ble to provide up-to-date altitude information on its large display (this could be read from other screens) In the confusion, the Airbus which leveled off at 12,500 feet was taken to be an F-14 fighter descending to attack! ‘User Hostile’ example Poor HCI can lead to User Hostile systems rather than User Friendly ones †¦ John has a stereo system with a matched set of components made by the same manufacturer: a receiver, a CD player, and a cassette deck, stacked in that order. They all have the on/off button on the left side. Every time John goes to turn off all three components, he presses the top left button on the receiver, which turns it off; then he presses the top left button on the CD player, which turns it off; then, naturally, he presses the top left button on the cassette deck which pops open the cassette door. It’s obvious †¦It seems obvious that the manufacturer could have improved the interface putting all three buttons in the same locatio n But it clearly wasnt obvious to the systems designers!! Most actions used to accomplish tasks with an interface are quite obvious to people who know them, including, of course, the software designer. But the actions are often not obvious to the first-time user. Another example †¦ Imagine a first-time user of a computer 1. he has been shown how to login to the system 2. has done some work 3. is now finished with the computer for the day ? Experienced computer users will find it obvious that a logout command is needed. But it may not occur to first-time users that a special action is required to end the session. People dont log out of typewriters or televisions or video games, so why should they log out of computers? Learning to predict problems like these by taking the users point of view is a skill that requires practice. Who studies HCI? (1) Multi-discipline field †¦ Who studies HCI? (2) Conclusion (1) HCI studies Interaction between users amp; computer systems In order to build systems which are: Usable Safe Efficient Effective Enjoyable Conclusion (2) Important points to keep in mind †¦ 1. You need a lot of common sense 2. You must be ready to accept criticism 3. Think ‘user’ 4. Try it out (They know what they want! ) 5. Involve the users 6. Iterate Exercise If we take a toaster Describe: the users the machine seems to be designed for; the tasks and subtasks the machine was evidently designed to support; the interface part of the machine; the part of the machine that is NOT the interface. What about an electric drill