Development of Vehicle Occupant Head Movement Envelope for Indian Population

Recent trends in vehicle occupant protection have led to renewed interest in the perception of Roominess such as headroom, shoulder room and foot room etc. Occupants head room in vehicles is currently measured using tools, procedures and definitions described in SAE J1052 and J1100. “Head Position Contours” defined in SAE J1052 are useful in establishing accommodation requirements for head space [1]. With respect to the Indian Anthropometry database, the head position contour as per SAE J1052 will not be appropriate with Indian population. With this objective in mind a head movement envelope is generated using the software - RAMSIS Digital manikin. RAMSIS is widely used by Automobile Manufacturers for Digital Human Modeling. The head movement envelope is a collation of different movements of head during driving condition. Possible head movements for a seated occupant in a vehicle when the vehicle is in driving condition are, (a) left/ right rotation, (b) Turn left/ right: look across a cross way, (c) Side swings: Sharp turns, side shakes and (d) Up/Down vibrations: Small bumps. This will help in defining the head movement area to be protected around the occupant head mainly for passenger cars.