An introduction to chord input
Upcoming SlideShare
Loading in...5

An introduction to chord input



A brief introduction to chord input - an alternative input style.

A brief introduction to chord input - an alternative input style.

Note: this presentation is also available on here under my old account.



Total Views
Views on SlideShare
Embed Views



1 Embed 1 1



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment
  • Stenotype = 300 wpm – faster than ANY other input technique (including voice recognition).

An introduction to chord input An introduction to chord input Presentation Transcript

  • Alternative Input: Striking a new Chord Stephen Nicholas 18-Oct-09
  • Agenda
    • About Me
    • What is Chord Input?
    • Why Chord Input?
    • Drawbacks
    • Examples
  • About Me
    • Stephen Nicholas
    • E-mail: [email_address]
    • @ sd_nicholas
    • ~2 Years
    • Automated GUI Testing
    • Developer on Microbroker
    • BSc Computing Science
    • 3 rd Year Project: An Investigation into Chord Input
  • What is Chord Input?
    • An input technique where, in addition to using single key presses, a user can use multiple simultaneous key presses to enter information.
    • Similar to playing a chord on a piano.
    • Examples:
      • ‘ Ctrl’ + ‘S’ to save a document
      • Braille Keyboard
      • The Microwriter
    • Reported to date back to 1836.
  • Why Chord Input?
    • Allows for a greater number of input combinations from a smaller number of keys.
      • 5 keys = 2 5 – 1 = 31 input combinations. A-Z, space and some modifiers.
      • 6 keys = 2 6 – 1 = 63 input combinations.
    • ‘ Keyboards’ can be made much smaller.
    • Efficient one-handed text entry.
    • Input speeds can match and exceed traditional QWERTY.
    • Potential uses:
      • On mobile devices.
      • Users with disabilities.
      • Reducing RSI.
  • Drawbacks
    • Uses encoded input schemes.
    • Can’t hunt and peck.
    • Longer learning times and higher initial error rates than QWERTY.
    • This can discourage users.
    • Can require good co-ordination and fine motor skills.
  • Examples
    • First introduced by Cy Endfield in 1978.
    • Portable chording device that had some commercial success in the 1980s.
    • Speeds up to 40 words per minute after ~7 months practice.
    • Encoding scheme with strong mnemonic element.
    • Recently ‘re-developed’ as the Cy-Key.
    – The Microwriter
  • Examples – The IBM Chord Keyboard
    • 10 main keys with overlapping dimples.
    • Supports hunting and pecking.
    • 4407 combinations using modifier keys on the thumb.
    • ~40 words per minute after several months practice.
    • Allows multiple letters to be entered at once:
    /I/n/ thi/s/ se/g/me/nt/ of/ te/xt/ the/ cho/rd/ bo/und/ar/i/es/ ha/ve/ be/en/ s/ho/wn/ by/ li/ne/s/.
  • Examples – The Twiddler
    • 3 x 4 buttons.
    • Designed for one-handed use.
    • ~80,000 unique combinations.
    • Use additional chords to enter groups of multiple characters.
    Examples – ChordTap
    • Uses normal phone key pad.
    • 3 additional keys to distinguish between the letters on each key.
    • Approx twice as fast as normal multi-tap.
  • Examples – The Cyclic Keyboard
    • Extension of scanning input.
    • Explores a temporal dimension.
    • Uses a number of memorable phrases to aid learning.
    • Could be extended to use more complex chords.
    • Potential 217 combinations, with 7 time periods.
    Key 5 Key 4 Key 3 Key 2 Key 1 T 5 T 4 T 3 T 2 T 1 T 0 O Z N C E B I I A H E M W V S K O A I A U T L R U J A F P Q T 6 X E G Y D
  • Summary
    • Traditional text entry methods are becoming less suitable for mobile devices.
    • Chord Input could help: it allows for quick, efficient, one-handed text entry.
    • Been around for a while.
    • Now coming of age.
    Any Questions? Thanks for listening @ sd_nicholas [email_address]