Introducing User-Centered Systems Design - Foundations for Designing User-Centered Systems - page 17

Fig. 1.4 An input glove.
(Photo taken by and used
with permission of Georgios
Christou)
Table 1.3 Example usability issues arising from the anthropometric level
• Providing normative data on limb sizes, body weight/height, and so on
• Providing descriptions of how sensitive touch is for input and output, particularly for the hands
• Measurement of muscle strain (to assess length of time on a particular job)
• Measurement of posture during particular tasks (to facilitate redesign of equipment)
the size of briefcases, and laptops weighed 30 pounds; these failed to be as popular
as expected partly because they were not small enough.
These issues are equally important in the design of mobile devices. Weight and
button size are important for their usability and the perceived usability for their
marketing. These issues will be more important for reality-based interfaces, where
computing is embedded into objects such as passports, children's toys, and objects
that have RFID tags which allow them to be tracked. These interfaces include both
computational aspects as well as the physical nature of the objects and the
opportunities and constraints that physical realization provides.