Body scanning

Abstract

Describes research designed to examine the effects of subject positioning on the accuracy of body scan data. A body measurement system developed by the Textile Clothing Technology Corporation was used to acquire two scans from each of 72 subjects. The subjects were instructed to continue to breathe normally and stand with their feet shoulder‐width apart. The two scans were compared and statistical analysis was performed to determine the precision of the results and whether this lack of standardization affected the data. Physical measurements were also obtained from each subject and served as a basis for comparison to the scanned measurements. Since physical measurements are the current accepted “true value”, these measurements determined the level of accuracy of scanned data. Three separate scans of 72 different subjects were taken at various levels of breathing and at various foot positions to determine the effect of the variables. This study certainly indicates that respiration and foot placement has a significant effect on body scan data. It was established that the scan data rendered by the software does have precision, but lacks accuracy when compared against physical measurements. This may be owing to the inaccuracies of the physical measurement process or to differences in measurement location between the anthropometrist and the 3D measurement extraction software. Information detailing the level of accuracy and precision that can be obtained with scanning software and how respiration and subject positioning can affect the data are included.

Development of a positioning aid to reduce postural variability and errors in 3D whole body scan measurements

“…ISO 20685 stipulates that "for all postures, quiet respiration (normal breathing) should be adopted". This is in line with the findings of the study conducted by Mckinnon and Istook (Mckinnon and Istook, 2002), who scanned subjects holding their breath at different inhalation levels and when breathing normally. They found that humans are unable to reliably replicate a certain respiration level and that continuing breathing normally during the scanning process compromises the data integrity least.…”

“…Accuracy and precision of the data ascertained with 3D body scanners are influenced by the factors listed in Figure 1 and are broadly split into two main categories: Technical Variability and Human Variability Mochimaru, 2011, 2008;Mckinnon and Istook, 2002): Previous studies have shown that body dimensions extracted from 3D body scans regularly fail to satisfy the accuracy requirements laid down in ISO 20685 for the use in anthropometric databases (Han et al, 2010;Mckinnon and Istook, 2002). Thus, those of the aforementioned factors need to be identified, which potentially inhibit achieving the desired level of accuracy and precision.…”

“…Since they are either standing or sitting unrestrained on the scanner platform, variations in the posture due to body sway and the user's inability to replicate postures are inevitable. Thus, in a number of studies postural variability was found to compromise the integrity of the scan derived anthropometric data considerably (Han et al, 2010;Mckinnon and Istook, 2002).…”

“…Although a number of researchers called for measures to stabilise the human posture during the scanning process Mckinnon and Istook, 2002;Tomkinson and Shaw, 2013), so far only a few attempts have been made to counter body sway and poor posture replication. Exceptions are handles to stabilise the arm posture that can be found in body scanners manufactured by TC 2 and Size Stream or rudimentary fixation elements used in studies conducted by Reed and Guitierrez (Guitierrez, C. M. and Gallagher, 2008;Reed, 2012).…”

Comparison of 3D laser-based photonic scans and manual anthropometric measurements of body size and shape in a validation study of 123 young Swiss men

“…When measured manually, the physical contact and proximity to the measurer might influence body posture and contraction of the trunk area of the probands resulting in smaller values (Jaeschke, Steinbrecher & Pischon, 2015). In the case of hip circumference, the standard scanning posture with legs hip-width apart might enlarge the resulting measurements (McKinnon & Istook, 2002). In general, the hand-held tape measurements have a tendency to compress the circumference caused by too much tension and thus reduce the values (Wang et al, 2006).…”