Alongside advancements in automated vehicle technologies, occupants within vehicle compartments are enjoying increased freedom to relax and enjoy their journeys. For instance, reclined seating postures have become more prevalent and comfortable compared to upright seating when Highly Automated Vehicles (HAVs) are introduced. Unfortunately, most Anthropomorphic Testing Devices (ATD) do not support reclined postures.
THOR-AV 50M is a specially designed dummy for reclined postures. As a crucial tool for developing safety restraint systems to protect reclined occupants, the first question is how to position it correctly on a reclined seat before impact testing.
In this study, classical zero gravity seats were selected. H-point coordinators of selected seat at 25°, 40° and 60° seatback angle were measured and compared by using H-point machine (HPM) even though current HPM was not designed for reclined seat. THOR-AV 50M with loosened joints, served to simulate human relaxation fully when seating on a seat, to explore the most comfortable position, there were two ways of seat adjusting from 25° to 40° and 60°, H-point coordinators of THOR-AV 50M at 40° and 60° were measured, related H-point could be regarded as the most comfortable position. By comparing the measured H-point coordinators of THOR -AV 50M and HPM at 40° and 60°, authors found that deviations were within current regulatory requirement. This finding indicated that the target of H-point of THOR-AV 50M at reclined seating position could be pre-defined by HPM. Therefore, a procedure for positioning the dummy in a reclined seat was developed. This paper provides an explanation of the rationale behind the method by using both physical and virtual dummy finite element models. It serves as a valuable reference for potential updates to related standards and protocols to incorporate reclined seating positions in the future, makes up for blanks in automotive industry.