The following usability issues, if ignored in practice, can hinder the development of
any collaborative SUI-based application. The y must be addressed each time an SUI-
based system is to be considered.
The user’s stylus, fingers, and hands may partially occlude the interface.
Interface elements may be difficult to select because of stylus, finger, or hand
Users may suffer fatigue due to the range of human motion required.
The screen surface can be damaged or dirty.
There may be a lack of tactile feedback from passive screen surfaces.
Calibration between the display (projector or LCD) and the sensing elements
can become misaligned.
This chapter provided an over view of the core research and developments in
multitouch display systems for surface user and face-to-face collaborative interfaces.
We showed how these developments have impacted each other and the relative
merits of each. We also discusse d the notion of a surface user interface and how var-
ious forms of technology can be used to realize it for collaborative interaction.
Tables 1.1 through 1.3 illustrated the types of gesture, action, and description SUIs
should support. The chapter concluded with design guidelines for SUI’s and how
they can be applied to future interface design.
The ultimate goal of surface user interfaces in collaborative face-to-face activities is
for people not to feel they are using a computer; instead, the visual elements should
naturally support their actions. Ultimately, SUIs will become so commonplace in
everyday life that no one will notice their presence. They will be aesthetic, powerful,
and enhance our lives but so too will they be commonplace, obvious, and boring.
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