Twenty Years of Eye Typing: Systems and Design Issues Tampere Unit for Computer Human Interaction Päivi Majaranta & Kari-Jouko Räihä 25 March 2002 ETRA2002

Contents Introduction Typing by gaze Keyboard layout Focus Feedback Selection Keyboard layout Customization and context of use Typing vs. communication System level issues Discussion 1

Introduction Eye Typing means producing text by using the point of gaze Needed by people with severe disabilities Control of the eyes may be the only option Need for a communication system is acute Focus on producing text But: considerations of communication strongly present, since most of the systems are designed for use as communication systems 2

Typing by gaze A typical eye typing system has an on-screen keyboard an eye tracking device to record eye movements a computer to analyze gaze behavior To type by gaze the user focuses on the letter s/he wants to type gets feedback by the system (e.g. highlight) selects the item in focus (e.g. by a switch) QuickGlance http://www.eyetechds.com 3

Focus Move focus by looking at the wanted item Mouse emulation moving the cursor by moving eyes (& head) Dwell time continuous fixations on an item (< 1 s) Shift focus by short gaze glances eyes as switches needed if difficulties with fixating EPCOS, Frietman and Kate 1978 Shein, 1997 4

Feedback Currently focused item Cues for dwell time duration Successful selection Visual highlighting, changing colors moving, animated, shrinking cursors Auditory beep, click spoken (letters, words, sentences) Proper is feedback especially important for disabled who may have never controlled much anything EagleEyes, Gips and Olivieri 1993 ERICA, Lankford, ETRA2000 5

Selection Focusing and selecting may be linked Dwell time May not be perceived as separate operations Dwell time Item is focused and subsequently selected May be interrupted by looking away before the time runs out Blinks, winks, wrinkles Must be separated from natural blinks Additional switches Also, eyes as switches (with scanning) Off-screen targets VisionKey, Khan et al. 1995 6

Keyboard layout QWERTY not always best Items must be large enough Alphabetic may be faster to learn Most common letters may be grouped together Items must be large enough  Not much space left for text and other items Accuracy depends on eye tracking device, screen resolution, distance from the user The bigger the better up to ~4 degrees Items can be grouped to selection menus T9, probabilistic character layout EagleEyes, Gips & Olivieri 1996 This is the text f_ A to Z Delete O I A 6 most likely words U R L Space Type-To-Talk, Hansen et al., 2001 7

Customization and context of use The skills and needs of the users vary a lot Customizable features Dwell time duration Keyboard layout size, color, location, content, … Cursor appearance and functioning Sound (on/off, volume, earcons, speech) Possibility to disengage eye-control Integration to other applications Control Windows/Macintosh zooming, screen magnifiers, fish-eye views QuickGlance EyeCons, Rasmusson, CSUN99 8

Typing vs. communication Eye typing is slow Only one or a few words per minute Hard to have a conversation! Methods to speed up eye typing Phrases for everyday usage Sentence buffers “please give me” + “water” Character & Word prediction Dictionaries and predefined grammars New methods, like Dasher  up to 10-20 wpm Communicative icons Not all can (learn to) read and write! LC Eyegaze, Chapman 1991 Salvucci, 1999 9

VisionKey, http://www.eyecan.ca System level issues Virtual keyboards and communication aids No need to redo well-done work Many features already implemented “sticky keys”, word prediction, customization environmental control, integrated speech Portability Possibility to attach a wheelchair Size Sensitivity to body movements Changing lighting conditions EagleEyes, www.cs.bc.edu/~eagleeye VisionKey, http://www.eyecan.ca 10

Eye Communication Systems BlinkWriter, Murphy et al., 1993, EagleEyes, Gips et al., 1993, Boston College, MA EPCOS & EYE-SISTANT, Frietman et al., 1984, TU-Delft, Holland ERICA, Hutchinson et al., 1987, Univ. Virginia EYECOM, Rosen and Durfee, 1987 EYE-gaze, Tokorozawa, Japan Eye-Switch Controlled Communication Aids, Kate et al., 1979, TU-Delft, Holland EyeScan, Eulenberg et al., 1985 EyeTyper, Friedman et al., 1981 EyeWriter, Wiesspeiner et al., 1999, Graz, Austria LC EyeGaze, Chapman et al., 1991, LC Technologies, Virginia Quick Glance, Rasmusson et al., 1999 SiVHa, Blanco et al., 1998, Univ. Navarra, Spain Type-To-Talk, Hansen et al., 2001, IT-University Copenhagen, Denmark Viserg Eye Mouse, Istance et al., 1993, Univ. Leicester, UK VisionKey, Kahn et al., 1995, Ottawa Ontario, Canada VISIOBOARD, EU/Telematics project, 2000 … 11

Discussion Further development still needed Typing issues not been studied in detail methods for editing text selecting a chunk of text scrolling text fast undo methods improving typing rate interaction between virtual keyboard and text field usefulness of various forms of feedback, ... How to start up (re)calibration? Eye typing provides a rich set of issues for study from practical point of view: to develop more usable systems from research point of view: to understand gaze communication task 12

Thank you for your attention! Questions? curly@cs.uta.fi http://www.cs.uta.fi/hci/gaze PS. From our web page you will find an updated list of eye typing systems, links to their homepages, extra info, etc. 13