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HCI - Interaction Devices

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					Interaction Devices
Human Computer Interaction
     CIS 6930/4930
   Section 4188/4186
          Interaction Performance
►   60s vs. Today
     Performance
        ► Hz   -> GHz
     Memory
        ►k   -> GB
     Storage
        ►k   -> TB
     Input
        ► punch cards ->
        ► Keyboards, Pens, tablets, mobile
          phones, mice, digital cameras, web
          cams
     Output
        ► 10 character/sec
        ► Megapixel displays, color laser,
          surround sound, force feedback, VR
►   Substantial bandwidth increase!
              Interaction Performance
►   Future?
      Gestural input
      Two-handed input
      3D I/O
      Others: voice, wearable, whole
       body, eye trackers, data gloves,
       haptics, force feedback
      Engineering research!
      Entire companies created
       around one single technology
►   Current trend:
      Multimodal (using car
       navigation via buttons or voice)
      Helps disabled (esp. those w/
       different levels of disability)
             Keyboard and Keypads
►   QWERTY keyboards been
    around for a long time
       (1870s – Christopher Sholes)
       Cons: Not easy to learn
       Pros: Familiarity
       Stats:
         ► Beginners:   1 keystroke per
           sec
         ► Average office worker: 5
           keystrokes (50 wpm)
         ► Experts: 15 keystrokes per
           sec (150 wpm)
►   Is it possible to do better?
    Suggestions?
               Keyboard and Keypads
►   Look at the piano for possible
    inspiration
►   Court reporter keyboards (one
    keypress = multiple letters or a
    word)
      300 wpm, requires extensive
       training and use
►   Keyboard properties that matter
      Size
         ► large - imposing for novices,
           appears more complex
         ► mobile devices
      Adjustable
         ►   Reduces RSI, better
             performance and comfort
      Mobile phone keyboards,
       blackberry devices, etc.
►   QWERTY
                      Keyboard Layouts
      Frequently used pairs far apart
      Fewer typewriter jams
      Electronic approaches don‟t jam.. why
       use it?
►   DVOARK (1920s)
        150 wpm->200 wpm
        Reducing errors
        Takes about one week to switch
        Stops most from trying
►   ABCDE – style
      Easier for non-typists
      Studies show no improvement vs.
       QWERTY
►   Number pads
      What‟s in the top row?
      Look at phones (slight faster), then look
       at calculators, keypads
►   Those for disabled
        Split keyboards
        KeyBowl‟s orbiTouch (screenshot)
        Eyetrackers, mice
        Dasher - 2d motion with word prediction
                                        Keys
►   Current keyboards have been
    extensively tested
        Size
        Shape
        Required force
        Spacing
►   Speed vs. error rates for
    majority of users
►   Distinctive click gives audio
    feedback
      Why membrane keyboards are
       slow (Atari 400?)
          ► Environment hazards might
            necessitate
          ► Usually speed is not a factor
                      Keys Guidelines
►   Special keys should be denoted
►   State keys (such as caps, etc.)
    should have easily noted states
►   Special curves or dots for home
    keys for touch typists
►   Inverted T Cursor movement
    keys are important (though
    cross is easier for novices)
►   Auto-repeat feature
      Improves performance, but only
       if repeat is customizable (motor
       impaired, young, old)
►   Two thinking points:
      Why are home keys fastest to
       type?
      Why are certain keys larger?
       (Enter, Shift, Space bar)
►   This is called Fitt’s Law
          Keypads for small devices
►   PDAs, Cellphones, Game consoles
►   Fold out keyboards
►   Virtual keyboard
►   Cloth keyboards (ElekSen)
►   Haptic feedback?
►   Mobile phones
      Combine static keys with dynamic soft
       keys
      Multi-tap a key to get to a character
      Study: Predictive techniques greatly
       improve performance
      Ex. LetterWise = 20 wpm vs 15 wpm
       multitap
►   Draw keyboard on screen and tap w/ pen
      Speed: 20 to 30 wpm (Sears ‟93)
►   Handwriting recognition (still hard)
      Subset: Graffiti2 (uses unistrokes)
       Pointing Devices
► Direct manipulation needs some pointing device
► Factors:
      Size of device
      Accuracy
      Dimensionality
►   Interaction Tasks:
      Select – menu selection, from a list
      Position – 1D, 2D, 3D (ex. paint)
      Orientation – Control orientation or provide direct
       3D orientation input
      Path – Multiple poses are recorded
          ►   ex. to draw a line
      Quantify – control widgets that affect variables
      Text – move text
►   Faster w/ less error than keyboard
►   Two types (Box 9.1)
      Direct control – device is on the screen surface
       (touchscreen, stylus)
      Indirect control – mouse, trackball, joystick,
       touchpad
                Direct-control pointing
►   First device – lightpen
      Point to a place on screen and press a
       button
      Pros:
         ►   Easy to understand and use
         ►   Very fast for some operations (e.g.
             drawing)
      Cons:
         ►   Hand gets tired fast!
         ►   Hand and pen blocks view of screen
         ►   Fragile
►   Evolved into the touchscreen
      Pros: Very robust, no moving parts
      Cons: Depending on app, accuracy
       could be an issue
         ►   1600x1600 res with acoustic wave
      Must be careful about software design
       for selection (land-on strategy).
         ►   If you don‟t show a cursor of where you
             are selecting, users get confused
      User confidence is improved with a
       good lift-off strategy
         Direct-control pointing
► Primarily   for novice
  users or large user
  base
► Case study: Disney
  World
► Need to consider those
  who are: disabled,
  illiterate, hard of
  hearing, errors in
  usage (two touch
  points), etc.
            Indirect-Control Pointing
►   Pros:
     Reduces hand-fatigue
     Reduces obscuration problems
►   Cons:
     Increases cognitive load
     Spatial ability comes more into play
►   Mouse
     Pros:
        ►   Familiarity
        ►   Wide availability
        ►   Low cost
        ►   Easy to use
        ►   Accurate
     Cons:
        ►   Time to grab mouse
        ►   Desk space
        ►   Encumbrance (wire), dirt
        ►   Long motions aren‟t easy or obvious (pick up and replace)
     Consider, weight, size, style, # of buttons, force feedback
          Indirect-Control Pointing
► Trackball
     Pros:
        ► Smallphysical footprint
        ► Good for kiosks
►   Joystick
     Easy to use, lots of buttons
     Good for tracking (guide or
      follow an on screen object)
     Does it map well to your
      app?
►   Touchpoint
     Pressure-sensitive „nubbin‟ on
      laptops
     Keep fingers on the home
      position
         Indirect-Control Pointing
► Touchpad
   Laptop mouse device
   Lack of moving parts,
    and low profile
   Accuracy, esp. those w/
    motor disabilities
► Graphics    Tablet
     Screen shot
     comfort
     good for cad, artists
     Limited data entry
       Comparing pointing devices
►   Direct pointing
     Study: Faster but less accurate than indirect (Haller ‟84)
►   Lots of studies confirm mouse is best for most tasks for
    speed and accuracy
►   Trackpoint < Trackballs & Touchpads < Mouse
►   Short distances – cursor keys are better
►   Disabled prefer joysticks and trackballs
     If force application is a problem, then touch sensitive is preferred
     Vision impaired have problems with most pointing devices
        ► Use multimodal approach or customizable   cursors
        ► Read Vanderheiden ‟04 for a case study
►   Designers should smooth out trajectories
►   Large targets reduce time and frustration
                 Example
     fastest places to click on for a right-
► Five
 handed user?
                  Example
► What   affects time?
                                    Fitts‟s Law
► Paul Fitts (1954) developed a model of human hand
  movement
► Used to predict time to point at an object
► What are the factors to determine the time to point to
  an object?
        D – distance to target
        W – size of target
►   Just from your own experience, is this function linear?
        No, since if Target A is D distance and Target B is 2D
         distance, it doesn‟t take twice as long
        What about target size? Not linear there either
►   MT = a + b log2(D/W + 1)
      a = time to start/stop in seconds (empirically
       measured per device)
      b = inherent speed of the device (empirically
       measured per device)
      Ex. a = 300 ms, b = 200 ms/bit, D = 14 cm, W =
       2 cm
           ►   Ans: 300 + 200 log2(14/2 + 1) = 900 ms
      Really a slope-intercept model
                            Fitts‟s Law
► MT      = a + b log2(D/W + 1)
     a = time to start/stop in seconds (empirically measured
      per device)
     b = inherent speed of the device (empirically measured
      per device)
     Ex. a = 300 ms, b = 200 ms/bit, D = 14 cm, W = 2 cm
              300 + 200 log2(14/2 + 1) = 900 ms
         ► Ans:
     Question: If I wanted to half the pointing time (on average), how
      much do I change the size?
►   Proven to provide good timings for most age groups
►   Newer versions taken into account
       Direction (we are faster horizontally than vertically)
       Device weight
       Target shape
       Arm position (resting or midair)
       2D and 3D (Zhai ‟96)
            Very Successfully Studied
►   Applies to
        Feet, eye gaze, head mounted sights
        Many types of input devices
        Physical environments (underwater!)
        User populations (even retarded and drugged)
        Drag & Drop and Point & Click
►   Limitations
        Dimensionality
        Software accelerated pointer motion
        Training
        Trajectory Tasks (Accot-Zhai Steering Law)
        Decision Making (Hick‟s Law)
►   Results (what does it say about)
        Buttons and widget size?
        Edges?
        Popup vs. pull-down menus
        Pie vs. Linear menus
        iPhone/web pages (real borders) vs. monitor+mouse (virtual borders)
►   Interesting readings:
        http://particletree.com/features/visualizing-fittss-law/
        http://www.asktog.com/columns/022DesignedToGiveFitts.html
        http://www.yorku.ca/mack/GI92.html
    Precision Pointing Movement Time
►   Study: Sears and Shneiderman ‟91
     Broke down task into gross and fine components for small targets
     PPMT = a + b log2(D/W+1) + c log2(d/W)
        ►c  – speed for short distance movement
        ► d – minor distance
     Notice how the overall time changes with a smaller target.
►   Other factors
     Age (Pg. 369)
►   Research: How can we design devices that produce smaller
    constants for the predictive equation
     Two handed
     Zooming
                       Novel Devices
►   Themes:
      Make device more diverse
         ► Users
         ► Task
      Improve match between task
       and device
      Improve affordance
      Refine input
      Feedback strategies
►   Foot controls
      Already used in music where
       hands might be busy
      Cars
      Foot mouse was twice as slow
       as hand mouse
      Could specify „modes‟
          Novel Devices
►   Eye-tracking
     Accuracy 1-2 degrees
     selections are by constant
      stare for 200-600 ms
     How do you distinguish w/ a
      selection and a gaze?
     Combine w/ manual input
►   Multiple degree of freedom
    devices
     Logitech Spaceball and
      SpaceMouse
     Ascension Bird
     Polhemus Liberty and
      IsoTrack
                     Novel Devices
►   Boom Chameleon
     Pros: Natural, good spatial
      understanding
     Cons: limited applications,
      hard to interact (very
      passive)
►   DataGlove
     Pinch glove
     Gesture recognition
     American Sign Language,
      musical director
     Pros: Natural
     Cons: Size, hygiene,
      accuracy, durability
                            Novel Devices
►   Haptic Feedback
        Why is resistance useful?
        SensAble Technology‟s Phantom
        Cons: limited applications
        Sound and vibration are easier and
         can be a good approximation
          ►   Rumble pack
►   Two-Handed input
      Different hands have different
       precision
      Non-dominant hand selects fill, the
       other selects objects
►   Ubiquitous Computing and Tangible
    User Interface
      Active Badges allows you to move
       about the house w/ your profile
      Which sensors could you use?
      Elderly, disabled
      Research: Smart House
      Myron Kruger – novel user
       participation in art (Lots of exhibit
       art at siggraph)
                      Novel Devices
►   Paper/Whiteboards
     Video capture of annotations
     Record notes (special tracked pens
      Logitech digital pen)
►   Handheld Devices
     PDA
     Universal remote
     Help disabled
        ► Read LCD screens
        ► Rooms in building
        ► Maps
     Interesting body-context-sensitive.
        ► Ex.hold PDA by ear = phone call
          answer.
  Novel Devices
► Miscellaneous
   Shapetape – reports 3D
    shape.
     ► Tracks   limbs
► Engineer  for specific
  app (like a gun trigger
  connected to serial
  port)
   Pros: good affordance
   Cons: Limited general
    use, time
 Speech and Auditory Interfaces
► There‟s the dream
► Then there‟s reality
► Practical apps don‟treally require freeform
  discussions with a computer
   Goals:
     ► Low cognitive load
     ► Low error rates
► Smaller    goals:
   Speech Store and Forward (voice mail)
   Speech Generation
   Currently not too bad, low cost, available
    Speech and Auditory Interfaces
►   Bandwidth is much lower than visual displays
►   Ephemeral nature of speech (tone, etc.)
►   Difficulty in parsing/searching (Box 9.2)
►   Types
       Discrete-word recognition
       Continuous speech
       Voice information
       Speech generation
       Non-speech auditory
►   If you want to do research here, lots of research in the
    audio, audio psychology, and DSP field you should
    understand
         Discrete-Word Recognition
►   Individual words spoken by a specific person
►   Command and control
►   90-98% for 100-10000 word vocabularies
►   Training
     Speaker speaks the vocabulary
     Speaker-independent
►   Still requires
       Low noise operating environment
       Microphones
       Vocabulary choice
       Clear voice (language disabled are hampered, stressed)
       Reduce most questions to very distinct answers (yes/no)
          Discrete-Word Recognition
►   Helps:
        Disabled
        Elderly
        Cognitive challenged
        User is visually distracted
        Mobility or space restrictions
►   Apps:
      Telephone-based info
►   Study: much slower for cursor movement than mouse or keyboard
    (Christian ‟00)
►   Study: choosing actions (such as drawing actions) improved
    performance by 21% (Pausch ‟91) and word processing (Karl ‟93)
      However acoustic memory requires high cognitive load (> than hand/eye)
►   Toys are successful (dolls, robots). Accuracy isn‟t as important
►   Feedback is difficult
    Continuous Speech Recognition
►   Dictation
►   Error rates and error repair are still poor
►   Higher cognitive load, could lower overall quality
►   Why is it hard?
      Recognize boundaries (normal speech blurs them)
      Context sensitivity
      “How to wreck a nice beach”
►   Much training
►   Specialized vocabularies (like medical or legal)
►   Apps:
        Dictate reports, notes, letters
        Communication skills practice (virtual patient)
        Automatic retrieval/transcription of audio content (like radio, CC)
        Security/user ID
         Voice Information Systems
► Use human voice as a source of info
► Apps:
      Tourist info
      Museum audio tours
      Voice menus (Interactive Voice Response IVR systems)
►   Use speech recognition to also cut through menus
      If menus are too long, users get frustrated
      Cheaper than hiring 24 hr/day reps
►   Voice mail systems
      Interface isn‟t the best
►   Get email in your car
      Also helps with non-tech savvy like the elderly
►   Potentially aides with
      Learning (engage more senses)
      Cognitive load (hypothesize each sense has a limited „bandwidth‟)
          ►   Think ER, or fighter jets
              Speech Generation
► Playback speech (games)
► Combine text (navigation systems)
► Careful evaluation!
   Speech isn‟t always great
     ► Door  is ajar – now just a tone
     ► Use flash
     ► Supermarket scanners
   Often times a simple tone is better
   Why? Cognitive load
     ► Thuscockpits and control rooms need speech
     ► Competes w/ human-human communication
                   Speech Generation
►   Ex: Text-to-Speech (TTS)
►   Latest TTS uses multiple syllabi to make generated speech sound
    better
      Robotic speech could be desirable to get attention
      All depends on app
      Thus don‟t assume one way is the best, you should user test
►   Apps: TTS for blind, JAWS
►   Web-based voice apps: VoiceXML and SALT (tagged web pages).
      Good for disabled, and also for mobile devices
►   Use if
      Message is short
      Requires dynamic responses
      Events in time
►   Good when visual displays aren‟t that useful. When?
      Bad lighting, vibrations (say liftoff)
  Non-speech Auditory Interface
► Audio   tones that provide information
► Major   Research Area
   Sonification – converting information into audio
   Audiolization
   Auditory Interfaces
► Browsers    produced a click when you clicked on a
 link
     Increases confidence
     Can do tasks without visual cognitive load
     Helps figure out when things are wrong
     Greatly helps visually impaired
    Non-speech Auditory Interface
►   Terms:
     Auditory icons – familiar sounds
      (record real world sound and
      play it in your app)
     Earcons – new learned sounds
      (door ajar)
►   Role in video games is huge
     Emotions, Tension, set mood
►   To create 3D sound
     Need to do more than stereo
     Take into account Head-related
      transfer function (HRTF)
        ►    Ear and head shape
►   New musical instruments
     Theremin
►   New ways to arrange music
          Displays
► Primary Source of
  feedback
► Properties:
       Physical Dimension
       Resolution
       Color Depth and correctness
       Brightness, contrast, glare
       Power
       Refresh rate
       Cost
       Reliability
       # of users
          Display
        Technology
►   Monochrome displays
    (single color)
     Low cost
     Greater intensity range
      (medical)
►   Color
     Raster Scan CRT
     LCD – thin, bright
     Plasma – very bright, thin
     LED – large public displays
     Electronic Ink – new product
      w/ tiny capsules of negative
      black particles and positive
      white
     Braille – refreshable cells
      with dots that rise up
                    Large Displays
► Wall   displays
   Informational
     ► Control rooms, military, flight
       control rooms, emergency
       response
     ► Provides
           System overview
           Increases situational awareness
           Effective team review
     ► Old:   Array of CRTs
   Interactive
     ► Require  new interaction
       methods (freehand sketch,
       PDAs)
     ► Local and remote collaboration
     ► Art, engineering
   Large Displays
► Multiple   Desktop Displays
   Multiple CRTs or Flat panels for
    large desktops
   Cheap
   Familiar
   Spatial divide up tasks
   Comparison tasks are easier
   Too much info?
► HMD
► Eventually   -> Every surface a
  pixel
               Mobile device displays
►   Applications
     Personal
        ► Reprogrammable       picture
          frames
             Digital family portrait
              (GaTech)
     Business
        ► PDAs,   cellphones
     Medical
        ► Monitor   patients
     Research: Modality
      Translation Services (Trace
      Center – University of
      Wisconsin)
        ► As you move about it auto
          converts data, info, etc. for
          you
            Mobile device displays
►   Actions on mobile devices
     Monitor information and
      alert (calendar)
     Gather then spread out
      information (phone)
     Participate in groups and
      relate to individual
      (networked devices)
     Locate services and identify
      objects (GPS car system)
     Capture and then share info
      (phone)
              Mobile device displays
►   Guidelines for design
      Bergman ‟00, Weiss, ‟02
      Industry led research and design case studies
       (Lindholm ‟03)
      Typically short in time usage (except handheld
       games)
      Optimize for repetitive tasks (rank functions
       by frequency)
      Research: new ways to organize large
       amounts of info on a small screen
      Study: Rapid Serial Visual Presentation
       (RSVP) presents text at a constant speed
       (33% improvement Oquist ‟03)
      Searching and web browsing still very poor
       performance
      Promising: Hierarchical representation (show
       full document and allow user to select where
       to zoom into)
     Animation, Image, and Video
► Content quality has also greatly
  increased
► 3D rendering is near life-like
► Digital Photography is common
► Scanned documents
► Video compression
► Multimedia considerations for the
  disabled
► Printers
     3D Printers create custom objects
      from 3D models

				
DOCUMENT INFO
Description: Human Computer Interaction Devices such as Keyboard and Keypad, Pointing devices and their use how they interact, Fitt's Law, Direct and Indirect Pointing devices, speech and audio devices, types of devices, future technologies and mobile devices such as PDAs, Apple Phones e.t.c.