2007 PhD Thesis Final Revised.pdf - Curtin University

Figure 6.10 Omni Phantom (SensAble Technologies, 2004)
Tactile graphics tablets have also received much attention as a method of
conveying information from a visual monitor in a non-visual form. They usually
consist of a large rectangular set of pins which can be raised and lowered like those
in a refreshable Braille display. However, other approaches have used vibrating pins
or plastic bumps. Shaped memory alloys have also been used in the construction of
tactile graphics displays. An important benefit of tactile tablets is that they often
support multipoint interaction like that in the real world. That is, objects can be felt
with all fingers of both hands, rather than with the point of one stylus or by the
movement of a mouse. It is also highly useful in conveying spatial concepts such as
the height of graphs and the measurement of distances. This allows maximum use of
the restricted bandwidth available to the sense of touch. Tactile graphics tablets are
still experimental and are not currently available in the commercial marketplace.
Portable note-taking devices are also useful in providing portable computing
technology to blind and vision impaired users. Similar in functionality to a PDA and
in many cases running the same Operating Systems, portable note takers provide
office productivity tools such as word processing, contact management and Internet
facilities. The input is generally via either a standard or Braille keyboard. As the
device is for blind or low vision users, the output is audio speech rather than a screen
display. Examples of electronic note takers include the PACMate by Freedom
Scientific and the BrailleNote as seen in Figure 6.11. The BrailleNote also
incorporates a refreshable Braille display, wireless and GPS technologies.
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