Development of anthropometric specifications for the warrior injury assessment manikin (WIAMan)

Abstract

Data from a previous study of soldier posture and body shape were analyzed to develop anthropometric specifications for the Warrior Injury Assessment Manikin (WIAMan), an anthropomorphic test device (ATD) intended to represent a midsize male soldier for assessments of vehicle occupant protection in underbody blast. Target stature, body mass, and erect sitting height were established by reference to the median values for these dimensions in a recent Army study. Body landmark locations from 100 soldiers with a wide range of body size obtained in a single squad seating condition were analyzed using regression methods to establish target surface landmark and internal joint center locations. Laser scan data from 126 men in up to four seated postures were analyzed using principal component analysis and regression to obtain a statistical model predicting body shape as a function of overall body dimensions and surface landmark locations. A subset of the target landmarks obtained in the squad posture analysis were used as input to the body shape model, resulting in a three-dimensional representation of the mean expected body shape for soldiers matching the target body dimensions in the reference seating condition. Small adjustments to the posture and shape were made to obtain a symmetrical posture with the thighs horizontal and legs vertical. Additional analyses of posture and CT data were conducted to estimate spine segment orientations and pelvis geometry.