Evaluation of Occupant Kinematics during Low- to Moderate-Speed Side Impacts 2020-01-1222
While nearly 50 percent of occupants in side-impact collisions are in vehicles that experience a velocity change (delta-V) below 15.0 kph (9.3 mph), full scale crash testing research at these delta-Vs is limited. Understanding occupant kinematics in response to these types of side impacts can be important to the design of side-impact safety countermeasures, as well as for evaluating potential interactions with interior vehicle structures and/or with other occupants in the vehicle. In the current study, two full-scale crash tests were performed utilizing a late-model, mid-size sedan with disabled airbags. The test vehicle was impacted by a non-deformable moving barrier on the driver side at an impact speed of 10.0 kph (6.2 mph) in the first test and then on the passenger side at an impact speed of 21.6 kph (13.4 mph) in the second test, resulting in vehicle lateral delta-Vs of 6.1 kph (3.8 mph) and 14.0 kph (8.7 mph), respectively. As can occur in real-world collisions, the initial impacts to the vehicle were followed by subsequent lower severity contacts. In both tests, Hybrid III 50th percentile male anthropomorphic test devices (ATDs) were restrained in the driver and right front passenger seats. The current study allowed for comparison of the near- and far-side occupant kinematics during the multiple vehicle contacts. The occupant kinematics were evaluated using high-speed video recordings of the collisions. Motion tracking was used to evaluate excursion magnitudes and excursion velocities during these collisions and demonstrated that, in general, the magnitudes of occupant excursion and velocity were greater in the higher-speed collision than in the lower-speed collision. Occupant motions relative to vehicle structures and relative to the other occupant were evaluated. In general, the kinematics included oscillatory responses of the ATDs following the initial motion toward the impact and return motion toward and beyond the original seated position. No significant occupant-to-occupant contact was seen in the current study, and head contact with vehicle side window glazing was only observed with the near-side ATD in the higher-speed impact where side curtain airbag deployment would have occurred.