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HCI Lecture 14

Special Issues: Ubiquitous computing

Hiroshi Shimodaira Key points:

–  Making the computer part of the environment –  Mobile devices –  Implicit input –  Ambient output –  Continuous interaction –  Issues for design and evaluation

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Introduction

  Human-computer interaction addresses the relationship between humans and computers, doing tasks in environments

  The focus should be on supporting human activities   Ideally, the computer would just be part of the background

environment in which we do the task   This concept has been called invisible, pervasive or ubiquitous

computing (Weiser, 1991)

Human

Task

Computer

Environment

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Introduction

  Computation beyond the workstation or desktop computer (fixed location, screen, keyboard & pointing device).

  Includes: –  Handheld, portable and wearable devices

•  Mobile phones, PDAs, digital cameras, sat-navs etc.

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Introduction

  Computation beyond the workstation or desktop computer (fixed location, screen, keyboard & pointing device).

  Includes: –  Handheld, portable and wearable devices

•  Mobile phones, PDAs, digital cameras, active badges etc.

–  Very different scales or styles of output •  Very small and very large displays, distributed, 3-dimensional •  Richer sounds, device actuation, ambient cues •  Augmented vs. virtual reality

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Introduction

  Computation beyond the workstation or desktop computer (fixed location, screen, keyboard & pointing device).

  Includes: –  Handheld, portable and wearable devices

•  Mobile phones, PDAs, digital cameras, sat-navs etc. –  Very different scales or styles of output

•  Very small and very large displays, distributed, 3-dimensional •  Richer sounds, device actuation, ambient cues •  Virtual or augmented reality

–  Novel forms of input •  Pen-based, touch based, proximity sensing •  Voice operated •  Tilt or motion sensing •  Implicit input – location, time, context

–  Embedded computers in other technologies •  Cars, washing machines, etc. •  Instrumented rooms, buildings, environments

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Introduction

  Often these factors interact:

Mobile device Smaller interface Alternative I/O

methods Reduced power and

functionality Specialised for certain functions Task specific

interfaces

Improved usability!

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Guidelines for Small Devices

  Should distinguish mobile (usable while moving) from portable (movable but need to be stationary to use successfully)

  Use(fulness) immediately apparent   Structure interface to task   Short cuts and flexibility   Minimise memory load   Use consistent screen templates   Provide a Back function on every screen   Selection is better than writing

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The Evolving iPod

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Small devices and the web

  Increasingly common for mobile devices to access the internet   Important constraints:

–  Smaller screens show less, so memory load increases –  Have awkward and error prone input methods –  Very wide variety of device specifications (screen size, resolution,

layout, interaction options) compared to standard desktop/laptop –  More connectivity and bandwidth issues –  People are unlikely to try to do all the tasks offered by the full site

using their mobile device

  Ideally should always make alternative ‘mobile’ site available, and make it easy to switch between this and the full site

  General principle: being able to do anything tends to make everything take longer to do.

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Norman’s “The Invisible Computer”

  “Personal” computer is “massive, impersonal, abrupt and rude”, used mostly to do social things and not for computing

  A device that does everything will be convenient but will probably perform worse than specialised devices: –  Swiss army knife vs. kitchen knife, corkscrew, screwdriver, scissors

  Also get incremental addition of features, amount of information stored (disk space), amount available (WWW), so can no longer make everything visible or discoverable

  Norman suggests technology should move towards “information appliances”, i.e. many items serving specific needs: –  ‘Home financial centre’ in right location with right connections –  Displays providing weather, news, sports (compare to clock) –  ‘Foreview’ mirror in cars for traffic, parking spots

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Norman’s “The Invisible Computer”

“Devices that are easy to use, not only because they will be inherently simpler, but because they fit the task so well that to learn the task is to learn the appliance.”

  Simplicity and visibility of function paramount

  Will require infrastructure to allow seamless information transfer between devices

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The iPhone

  Opposite direction: towards multipurpose device   Sensors: proximity, ambient light, accelerometer (orientation) and

touch screen – several advanced touch features   Loss of physical buttons removes ‘tactile landscape’

  See http://www.computerworld.com/ for usability test

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Natural interaction

  Much concern in HCI about finding more ‘natural’ forms of input   `Context aware’ computing suggests computers should be able

to recognise implicit inputs: –  E.g. walking into a space should be sufficient to announce your

presence and identity –  More generally, tracking the user’s location to supply them with

relevant information (satnav) –  Alternative forms of identification also have many obvious

applications (with varying requirements for reliability) –  Time is another implicit cue: could exploit to detect interest,

deviation from routine, even identity

  General idea is that input is a side-effect of doing the activity

  Automated capture as a background technology

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‘Invisible’ interaction

  Potential to ‘eliminate’ conscious interaction –  E.g. remove ticket sales by tracking where people went and

charging their accounts –  Verichip implant –  Identify patients in emergency situtation –  Other uses…?

  Replaces interaction programming problems with ethical problems –  Those without resources to be connected to system are

disenfranchised –  Removes option of anonymous interaction

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Natural interaction

  Tangible input devices – manipulate ‘ordinary’ physical object

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The world

Continuous interaction

  Obtaining natural interaction may involve collapsing the usual input/ output distinction

  `Continuous interaction’ emphasises the closed loop rather than stages of action

  On more extended time scales, includes thinking of HCI in terms of extended, ongoing activities rather than tasks that have a clear beginning and end –  Should support interruptions, concurrency etc.

Goals

Evaluation Sequence of actions

The world

Ongoing activity

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Design processes for continuous interaction

  Importance of ethnography in assessing user requirements (don’t trust post-hoc rationalisation)

what is wanted

analysis

design

implement and deploy

prototype

  Augment task analysis with:   Instantaneous information

requirements: will it be part of task, users memory, computers memory, or in environment?

  Trigger analysis: does next step occur immediately, after fixed or variable delay, or in response to external event?

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Evaluation of ubiquitous computing

  Some problems for evaluation

–  Hard to measure relevant variables –  Inappropriate to use methodologies that interfere with the normal

process (e.g. co-operative evaluation, lab experiment) –  Need long term analysis –  May be fuzzy usability criteria

  Standards and guidelines are developing for mobile devices, but still lagging for more immersive technologies

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References

Weiser, M. (1991) The computer for the 21st century. Scientific American, 265/3: 94-104

Norman, D. (1998) The Invisible Computer, MIT Press

Williamson, J. Murray-Smith, R. & Hughes, S. (2007) Shoogle: Multimodal Excitatory Interfaces on Mobile Devices, CHI 2007

  See also:

Dix et. al. sections 18.3, 18.4 chapter 20