Page 43 - Anthropometry, Apparel Sizing and Design

Anthropometric methods for apparel design: Body measurement devices and techniques 39

straight, the palms face backward, and the subject is breathing quietly. Lu et al. (2010)
examined the relationships between the arm posture and differences between scan-
derived and traditional measurements. They found that when the palms faced back-
ward rather than forward or to the side of the body, the space between the arm and
body was larger, and the differences between the scan-derived and traditional mea-
surements were smaller.

2.3.3 Scanning attire
Scanning attire should be neither too loose nor too tight and should be appropriate for
the purpose of the measurement. Fig. 2.8 shows the scan results of the same person
wearing three different garments. It is clear that the shape changes according to the
garment. ISO 20685-1 recommends that the subject being measured wears garments
that expose landmarks and a pattern that results in no side seams on the thigh. We
recommend a seam on the center back of the lower garment.
In most 3-D body scanners, dark colors cannot be captured. Long hair should be
pulled up using a rubber band and/or cap so that it does not hide the neck and shoulders
of the subject.

2.3.4 Comparability of scan-derived and traditional
1-D measurements
The quality of scan-derived measurements depends on the accuracy of the machine
and the performance of software for detecting and calculating the coordinates of
the center of marker stickers and for calculating body dimensions using landmark
locations. It also depends on the skill of the measurer to decide landmarks if the system
uses manually chosen landmark locations and on the skill of the operator to pick the
center of marker stickers using a mouse if the system uses manually chosen marker
locations. The quality of scan also depends on the body sway of the subject during
the scan because a human cannot stand completely still for 10s. The effects of body
sway are smaller when the scan time is shorter and the scan direction is from the top
down rather than from side to side. Many more factors affect the accuracy of scan-
derived 1-D measurements compared with traditional 1-D measurements in which
the skill of measure(s) is the dominant factor.
Scan-derived and traditional measurements have been compared in several studies
(e.g., Bougourd et al., 2000; Paquette et al., 2000; Han et al., 2010), but the criterion of
judging comparability is not always clear. ISO 20685-1:2018, first published in 2006,
establishes a protocol for evaluating the comparability between the scan-derived and
traditional 1-D measurements. In ISO 20685-1 the criterion of judgment is based on
interobserver differences of experienced anthropometrists in traditional 1-D measure-
ments. The procedure for evaluation is described in the succeeding text. See the orig-
inal document for details:
1. Measure N subjects (N 40) by traditional methods (measurer should be a skilled
anthropometrist) and by a 3-D body scanner.