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hands-free writing

Special Needs

Dasher is highly appropriate for computer users who are unable to use a two-handed keyboard. One-handed users and users with no hands love Dasher. The only ability that is required is sight.

Dasher can be driven using a mouse, a trackpad, a touchscreen, a rollerball, or a joystick - any two-dimensional pointing device that can take over the role of a mouse. A foot mouse and a head mouse are additional options.

It can also be driven using an eyetracker, giving a completely-hands-free writing system. After one hour's practice, some users are able to write at more than 20 words per minute using Dasher with an eyetracker

For a movie demonstrating Dasher with an eyetracker, see David Ward's movie page. [In the movie, David hits the space bar to start the program going, and after that he uses nothing but eyes.]

Compared to an eyetracker + visual keyboard, Dasher is

  • faster
  • more accurate
  • more fun

I am paralyzed from the shoulders down. What do I need to make Dasher work for me?
Do you have a PC? (Linux or Windows) Can you use a head-mouse? Or any other sort of mouse? Perhaps a mouth-stick that controls the mouse coordinates? If so, simply download the latest version of Dasher, and you should be able to write with Dasher.
If standard mice and head-mice are not an option, then you'll need an eyetracker that can take over control of the mouse.
We used a system from Eyetech called Quickglance.

Here are some links giving information about non-standard mouse devices.

  • Head-mouse From MouseVision Inc: VisualMouse (VM) software - widely used by disabled people, can be downloaded from free of charge. VM is a pointing device using a webcam that recognizes head motion (with no gear on the head). It works with Windows 98/ME/2000. [23/8/02.]
  • Smart-Nav Head mouse (was called TrackIR)
  • GyroMouse - Free space mouse - good for people with limited reach - and could probably be used as a head mouse or foot mouse.
  • Eyetrackers: Eyetech
  • Eyetrackers: Applied Science Laboratories

The Inference Group is supported by the Gatsby Foundation
and by a partnership award from IBM Zurich Research Laboratory
David MacKay
Site last modified Fri Oct 1 10:33:19 BST 2010