From Page 59
(4) Right. By making changes in the experimental prototype stage (concept
exploration), you have limited your costs by redesigning before the hardware
has actually been built.
The cost is a one-time cost.
Later it becomes
more difficult for a change to be accepted (red tape, if you will) and if a
change must take place, it will usually involve people rather than the
Thus far we've discussed test and evaluation assuming you knew why it
was done. Let's review the major purposes of HFE test and evaluation.
The following purposes of HFE testing are taken from Army Regulation
70-10 'Test and Evaluation During Development and Acquisition of Materiel.'
This document states that testing is conducted:
(1) To see how well (how validly) the
requirements, both technical and operational.
(2) To provide data to assess developmental and operational risk for
determine that faults
previous testing have
(4) To insure that all critical issues which are to be resolved by
testing have been considered.
AR 70-10 states that all testing (from the initial mock-up to the
completed system) is of interest.
Another way of stating the AR 70-10
purpose is to say the HFE tests and evaluations aim to improve the quality
of design decisions. Early in development when the various subsystems are
being developed, decisions regarding this design must be made.
testing helps in this process by providing information to improve the
quality of decision making.
Secondly, test and evaluation helps to integrate hardware and
This sounds like a major goal of human factors engineering in
general, doesn't it?
Since the discipline has not yet reached perfection,
we are unable to forecast precisely the best ways of integrating man and
Therefore, the best way to validate a design is by 'trying it
The third purpose of test and evaluation is to identify design
deficiencies early. This has already been explained above and is presented
graphically in Figure 37.1.
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