Dasher Developments

Automatic pointing calibration
Controlling Dasher by Breath or Buttons
Controlling Dasher by Tilt or Twist

Dasher/Owl interaction

The Owl is an invention of Martin King: an eyetracker without imaging, it works by measuring the intensity of reflected light from 8 directions in 8 directions around the eye. A prototype developed about 1987 gives excellent tracking of the eye with just four calibration points.

The Owl is so simple, it could be mass-produced as an eyetracker costing less than $10. It requires nothing to be fixed to the computer - no lights, no cameras. The user just attaches the Owl to his glasses.

The Owl's performance seems similar to that of more expensive eyetrackers. Should it be developed further? Creating a USB version of the device would probably require a couple more man-years of effort. One deficiency is that the Owl alone gives only relative eye-direction (so someone who wants to move their head around will need an additional head-orientation-tracker).

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David MacKay
Last modified: Tue Jan 24 19:06:58 2006