1. CATKey: Customizable and
Adaptable Touchscreen Keyboard
with Bubble Cursor-like Visual
Feedback
Kentaro Go, Yuki Endo*
Interdisciplinary Graduate School of Medicine and Engineering
Department of Computer Science and Media Engineering
University of Yamanashi
*HAL Laboratory
INTERACT 2007 1

2. History: Touchscreen Interfaces
Shneiderman, Sears
MacKenzie
Zhai
Ren
:
Sketchpad Multi-Touch Interaction
Sutherland @MIT, 1963 1980’s ~ 1990’s Experiments
Han @NYU, 2006
2

3. Touchscreen Application
Public Terminals Private Devices
iPhone, iPod touch Nintendo DS
PDA, Mobile phone
Table-size Shared Devices
Ticketing machine, ATM
Information KIOSK
Microsoft Surface
3

4. Touchscreen Keyboard
a fundamental application
4

5. Text Entry with Touchscreen Keyboard
1
The input speed is about of hardware keyboard
2
(Shneiderman, 1991; Sears et. al., 1993)
Hardware Touchscreen
keyboard keyboard
>
1
1 5
2

6. The CATKey project
• Goal: Increase the usability of touchscreen
keyboards with fingers
• Approach: Design a touchscreen
keyboard, which has
1. Customizable,
2. Adaptable, functions
3. User-friendly
6

7. CATKey: Customizable and Adaptable
Touchscreen Keyboard with Bubble
Cursor-like Visual Feedback
7

8. 1. Customizable Keyboard
Standard
QWERTY
Key Layouts
Customized
Key Layouts
8

9. 1. Customizable Keyboard
Maximize each key area
= Voronoi Diagram
(Himberg et. al., 2003)
W E R I O
T Y U P
Q D
S F K
G H J
A L
X C
V B N M
Z
SPACE
9

10. 2. Adaptable Keyboard
Automatic (on-line) adaptation of key
area based on user’s touch points
(Himberg et. al., 2003)
10

11. 3. User-friendly Keyboard
Provide the sensation of offset cursor
A simple application of the bubble cursor
(Grossman et. al., 2005) 11

12. 3. User-friendly Keyboard
Bubble cursor like visual feedback
12

13. Evaluation
• Ten students (male: 8, female: 2)
• Hardware keyboard vs. QWERTY touch
screen keyboard vs. CATKey
• Input forty pangrams
– Example: a quick brown fox jumped over the
lazy dog
• Text entry speed and Error rate
13

14. Text Entry Speed
in words per minute (wpm)
Text entry speed (wpm) 60
50
40 33.5 (10.3)
30
23.8 (4.6) 22.3 (4.7)
20
10
0
Hardware KBD QWERTY CATKey
Touchscreen keyboard
No significant difference
14

15. Error Rate
10
9
8
7
6.8 (2.8)
5.9 (1.8)
Error rate (%)
6
5
4 3.4 (1.9)
3
2
1
0
Hardware KBD QWERTY CATKey
Touchscreen keyboard
No significant difference
15

16. Users’ comments from Interview
• Positive comments
– I did not need to move my hands back and forth.
– In the Voronoi keys, the outside keys are lager in area
than the inside keys. It makes me type in very easily.
– I arranged the keys, that I am not good at typing in,
the easier positions to type in. It was good.
• Negative comments
– Some keys are over-adjusted. They became smaller
than I expected.
16

17. Conclusion
• CATKey: Customizable and Adaptable
Touchscreen
Keyboard with Bubble Cursor-like Visual Feedback
• Goal: Increase the usability of touchscreen
keyboards with fingers
• Approach: Design a customizable, adaptable,
user-friendly touchscreen keyboard
17

18. Future work
• Conduct further experiments on the
usability of CATKey
• Deal with the over-adjustment problem
• Explore key arrangements:
Metropolis arrangement Japanese arrangement
(Zhai et. al., 2000) Consonant Vowel
18

19. The optimum arrangement for …
A quick brown fox jumps over the lazy dog
Thank you ! 19