Parallel
Design
Primary Reference Source
Nielsen, J (1993) Usability Engineering. Academic Press, Boston.
Summary description
It is often helpful to develop possible system concepts with a parallel
process in which several different designers work out possible designs.
The aim is to develop and evaluate different system ideas before settling
on a single approach as a basis for the system.
In parallel design it is important to have the designers working independently,
since the goal is to generate as much diversity as possible. Therefore
the designers should not discuss their designs with each other until after
they have produced their draft design concepts.
When designers have completed their designs, it is likely that that
they will have approached the problem in radically different ways that
will give rise to different user systems. It is then possible to combine
designs and taking the best features from each.
It is important to employ parallel design for novel systems where they
is no established guidelines for how best the system should operate.
Although parallel design might at first seem like an expensive approach,
since many ideas are generated without implementing them, it is in fact
a very cheap way of exploring the range of possible system concepts.
Typical Application Areas
Parallel design is useful when there are quite different system concepts
under discussion and it is required to make a decision on one and one only.
It of course implies that some kind of working model or prototype is produced
by all the independent groups – see for instance Paper
Prototyping or Wizard of Oz.
Benefits
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Allows a range of ideas to be generated quickly and cost effectively.
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Parallel nature of the approach allows several approaches to be explored
at the same time, thus compressing the concept development schedule.
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The concepts generated can often be combined so that the final system benefits
from all ideas proposed.
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Only minimal resources and materials are required to convey product feel.
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The technique can be utilised by those with little or no human factors
expertise.
Limitations
Requires a number of design team members to be available at the same time
to produce system concepts. May become expensive if it becomes too elaborate.
Cost of use
The costs are mainly in time over the short period that design work is
being carried out. Time is also needed to compare parallel design outputs
properly so that the benefits of each approach are obtained.
Suitability for requirements engineering in Telematics
Partner NOMOS reports some successes
using this method; it should only be started if there is a shared understanding
in the project of how much resources will be put into the activity by each
partner/ competing solution provider.
How to get it
The best way to start is by reading Nielsen’s book. This approach is basically
a way of combining different prototyping approaches with some comparative
evaluation between candidate systems.
Procedure
The following procedure may be adopted for implementing this method:
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Define clearly the boundaries for the parallel design i.e. goal of system,
tasks that it should support, user characteristics etc.
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If possible agree on the format that the design will be produced in e.g.
on paper, in software.
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If design teams rather than individuals are being used, select groups that
have roughly equivalent skills.
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Set a clear time limit on the design phase.
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Agree on the criteria by which the design’s will be assessed.
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Allow sufficient time to carry out a fair comparison of the designs produced.
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Discuss each design separately and then discuss how different aspects of
the designs may be combined.