Comfortable Head and Neck Postures in Reclined Seating for Use in Automobile Head Rest Design 2019-01-0408
Advancements in vehicle automation will increase the importance of passenger comfort in road vehicles. Many design concepts for future vehicles emphasize reclined postures for resting and potentially sleeping. The head restraints in current reclining vehicle seats are designed primarily to meet safety requirements rather than to provide comfortable support in reclined postures. As part of a larger study, 24 men and women with a wide range of age and body size used adjustable foam pads to obtain comfortable, supported head and neck postures at seat back angles (SAE A40) that ranged from 23 to 53 degrees. Body landmark locations were recorded using a coordinate digitizer and a kinematic linkage of the skeleton was constructed. Posture was characterized by the side-view orientations of the thorax, neck, and head. The data demonstrated that comfortable neck postures at reclined seat back angles were more extended from 33 to 53 degrees of seatback recline than at 23 degrees. However, the position of the back of the head relative to the seat varied widely across individuals. These data provide the first quantitative guidance for the design of adjustable head rests suitable for highly reclined postures.
Matthew Reed, Sheila Ebert, Monica Jones
Univ. of Michigan - Ann Arbor, UMTRI, University of Michigan