<p>This body of research contributes to design praxeology: the study of process
and methodology with the intention to enhance the designer’s experience of the
human-centred design process by means of validating an optimum usability
testing environment for recreating the context of use early in the design
process.</p>
<p> </p>
<p>Usability testing will frequently make the difference
between an excellent product and a poor one.
Moreover, in certain fields such as medical device development or training,
the defence field or the automotive industry, such testing can literally be the
difference between life and death.
Unfortunately, design teams rarely have the luxury of either time or
budget to usability test every aspect of a design at every stage, and so
knowing where and when to devote time to testing, and the fidelity required for
accurate results, are all critical to delivering a good result. </p>
<p> </p>
<p>This thesis introduces research aimed at defining the
optimum fidelity of mixed-reality usability testing environments. It aims to develop knowledge enabling the
optimization of usability testing environments by balancing effort vs reward
and thus developing critical and accurate data early in the design process. This research also seeks to validate the findings
of an optimum environment in a final study and highlight the significance of
early usability testing in a simulated context of use.</p>
<p> </p>
<p>Testing in a traditional laboratory setting brings
advantages such as the ability to limit experimental variability, control
confidentiality and measure performance in detail. Its disadvantages over ‘in
the wild’ or field studies approaches tend to be related to ecological validity
and the small but vitally important changes in user behaviour in real-life
settings. Virtual reality and hybrid
physical-virtual testing environments should theoretically give designers the
best of both worlds, finding critical design flaws cheaply and early. However, many attempts have focused on
high-fidelity, technology-rich approaches that make them simultaneously more
expensive, less flexible and less accessible.
Additionally, the design literature does not take due account of
computer science and psychology when dealing with recreating environments. The final result is that they are less viable
and hence somewhat counter-productive. </p>
<p> </p>
<p>This thesis presents the results of testing at a variety of
fidelity levels within a mixed-reality testing environment, and offers a
contribution to new knowledge in determining how usability testing can be
maximized to recreate context of use environments early in the design
process. The findings recommend the use
of recreated environments throughout the design process complemented by
field/in-the-wild testing once the product is of high fidelity. </p>