The Morse Mouse Crossing Interface

1
The Morse Mouse Crossing Interface

• Why bother with point-and-click when I can just
  point?

2
Project Goals

• Develop a flexible, general purpose, text-capable
  user interface for our various pointing devices
• Head-tracking pointing device
• Eye-tracking pointing device
• Brain-Computer Interface
• People we are working with could use this right
  now

3
Design Criteria

• Minimize complexity
• Maximize generality
• Maximize generality
• Maximize compliance
• Minimize distance traveled
• Minimize time required

4
Alternative Approaches

• On-Screen Keyboards
• Simple-minded but complete
• Zooming Interface (Dasher)
• Brilliant but reactive
• Crossing Interface (Morse Mouse)
• Just right we hope.

5
Morse Code

• Well known and rather efficient
• Invented in 1836 by Samuel Morse
• Rates of 20 30 WPM achievable
• Entropy of English 4.14 bits / letter
• Average Morse codeword 5.56 bits
• Average Huffman codeword 4.35 bits

6
Morse Code Table
a - j --- s
b - k -- t -
c -- l - u -
d - m -- v -
e n - w --
f - o --- x --
g -- p -- y ---
h q --- z --
i r -
How de we map this to a graphical interface?
7
On-Screen Keyboard

• Many small areas - complex, difficult to resolve
• Uses dwell time in lieu of click - no snoozing!
• Irreducible minimum time and distance

8
Dasher Zooming Interface

• Elegant predictive language model
• Clickless, with no minimum distance
• Overwhelming (Attack of the killer alphabets)
• Text only no way to implement command buttons

9
Morse Mouse Crossing Interface

• Very simple only four core active areas
• Application specific command buttons
• Irreducible minima for time and distance reduced
  to minimum
• Pacing is controlled by the user

10
References

• Hansen, J P, Johansen, A S, Torning, K, Itoh, K,
  Aoki, H, 2004 Gaze typing compared with input
  by head and hand, Proc. Eye Tracking Res. App.
  Symp. (ETRA'04), pp 131-138.
• King, T W, 2000 Modern Morse Code in
  Rehabilitation and Education New Applications in
  Assistive Technology, Allyn and Bacon.
• Ward, D J, Blackwell, A F, and MacKay, D J C,
  2002 Dasher - A data entry interface using
  continuous gestures and language models.
  Human-Computer Interaction, vol 17 pp 2-3.