Abstract
This chapter reviews current concepts of sitting posture for thedesign of comfortable car seats. The objectives of seat design are discussed. Aspects of human geometry important in seat design are considered including body size, the human linkage system, position of the body and posture of the body. The effect of vibration is noted. Geometric features of seat design are divided into accommodation (seat size and adjustments for horizontal distance from controls, height and back angle) and comfort (stiffness, contour, climate, memory and features to promote occupant comfort). Each aspect is discussed and suggestions made for future research. Statistics of selected anthropometric size dimensions are provided.