The present study developed a sizing analysis system for head-related product designs based on the Civilian American and European Surface Anthropometry Resource (CAESAR) database of North Americans. A total of 2299 heads in the CAESAR database were manually edited and 26 anthropometric landmarks were marked on the edited 3D heads to measure 30 anthropometric dimensions related to head-related product designs. The 3D anthropometric sizing analysis system (3D-ASAS) developed in the study provides analysis functions of a sizing system and representative face models by considering a target product, a target population, the number of size categories, and key anthropometric dimensions based on the CAESAR head measurements. Further research to reduce the efforts of manual editing and landmarking of 3D body scan data is discussed for efficient application of the 3D-ASAS to the design process of various wearable products.

A revised pilot oxygen mask design was developed for better fit to the Korean Air Force pilots’ faces. The present study compared an existing pilot oxygen mask and a prototype of the revised mask design with 88 Korean Air Force pilots in terms of subjective discomfort, facial contact pressure, and slip distance on the face in high gravity. The average discomfort levels, facial contact pressures, and slip distance of the revised mask were reduced by 33%–56%, 11%–33%, and 24%, respectively, compared to those of the existing oxygen mask. The mask evaluation method employed in the study can be applied to ergonomic evaluation of full- or half-face mask designs.

This study aimed to compare a three-dimensional (3D) semiautomatic measurement protocol (3D-SAMP) that measures hand dimensions using a plaster hand and a 3D scanner with the conventional direct measurement protocol (DMP). An experiment was conducted to measure 52 dimensions of one hand by 20 measurers with three repetitions. The locations of landmarks attached to the plaster hand were automatically identified and then measurements of the hand dimensions were automatically extracted in the 3D-SAMP. Significant measurement differences with a range of 2.1 to 4.4 mm between the 3D-SAMP and the DMP were observed in 13 out of the 52 dimensions, and the 3D-SAMP showed better reliability than the DMP in terms of intra- and intermeasurer variability. The 3D-SAMP was found significantly faster and easier in hand measurement than the DMP (11.1 ± 3.5 min for 3D-SAMP and 17.8 ± 4.5 min for DMP; 5.2 ± 0.8 for 3D-SAMP and 4.3 ± 0.8 for DMP using a 7-point scale with 1 for very dissatisfied and 7 for very satisfied for ease of measurement) when fabrication (about 1 hr 10 min) and scanning (3 min) of a plaster hand were not considered. The proposed 3D-SAMP is applicable only to plaster hands available in hand measurement.

The present study developed and tested a new usability evaluation method which considers natural product-use motions. The proposed method measures both natural product-use motions (NMs) and actual product-use motions (AMs) for a product using an optical motion capture system and examines the usability of the product based on motion similarity (MS; %) between NMs and AMs. The proposed method was applied to a usability test of four vacuum cleaners (A, B, C, and D) with 15 participants and their MSs were compared with EMG measurements and subjective discomfort ratings. Cleaners A (44.6%) and C (44.2%) showed higher MSs than cleaners B (42.9%) and D (41.7%); the MSs mostly corresponded to the EMG measurements, which could indicate that AMs deviated from NMs may increase muscular efforts. However, the MSs were slightly different from the corresponding discomfort ratings. The proposed method demonstrated its usefulness in usability testing, but further research is needed with various products to generalize its effectiveness.