ATD Positioning Based on Driver Posture and Position

Current ATD positioning practices depend on seat track position, seat track travel range, and design seatback angle to determine appropriate occupant position and orientation for impact testing. In a series of studies conducted at the University of Michigan Transportation Research Institute, driver posture and position data were collected in forty-four vehicles. The seat track reference points currently used to position ATDs (front, center, and rear of the track) were found to be poor predictors of the average seat positions selected by small female, midsize male, and large male drivers. Driver-selected seatback angle was not closely related to design seatback angle, the measure currently used to orient the ATD torso. A new ATD Positioning Model was developed that more accurately represents the seated posture and position of drivers who match the ATD statures. Seat position is specified for each adult ATD size to match the mean predicted seat position of drivers matching the ATD reference stature. ATD torso orientation is set to the average driver torso orientation. The new positioning model places the ATDs in postures and positions that are more representative of drivers of similar size.