Development of Posture Prediction and Accommodation Models for Military Vehicles: Commander and Gunner Positions

Technical ReportAccurate information on warfighter posture and position is essential for the design of military vehicles for safety and effectiveness. In prior work, posture measurements from Soldiers were used to develop statistical posture- prediction and accommodation models for drivers in a range of configurations, including fixed heel point and fixed eye point. Models were also generated for a squad seating condition with no tasks. In the current study in the series, soldiers were measured in mockups representing commander and gunner positions. The commander position has an adjustable seatback angle, a keyboard, and a screen. The gunner condition is intended to simulate use of a remote weapons system and includes a seat with a fixed seat back angle, a joystick, and a screen. In each configuration, soldiers adjusted the screen and keyboard or joystick to obtain comfortable working postures, which were measured by recording the three-dimensional locations of body landmarks. Data were gathered with two ensembles: body armor vest and helmet (PPE level) and with the addition of a simulated body borne gear (BBG) rifleman kit representing the encumbered (ENC) soldier. Internal joint center locations were estimated from surface landmarks. Statistical posture-prediction models were developed using regression analysis to predict the locations of important landmarks, such as the hip joint centers, eyes, and knees. Population accommodation models were developed using parametric techniques developed in prior work. These models generate surface contours that can be used in design to accommodate a desired percentage of a vehicle occupant population. The models take into account the effects of population anthropometry, clothing and gear ensemble, and vehicle configuration. Contours were generated for the preferred and acceptable ranges of screen, keyboard, and joystick locations as well as eye location (eyellipse) and clearance contours for helmet, torso, elbow, knee, and boot.US Army Tank-Automotive Research and Development Centerhttp://deepblue.lib.umich.edu/bitstream/2027.42/175576/1/UMTRI-2021-7.pd