As part of a comprehensive plan to reduce the risk of death and serious injury in rollover crashes the National Highway Traffic Safety Administration (NHTSA) has reinitiated a program to characterize restraint system response in rollovers. A rollover restraint tester (RRT) is utilized to produce a 180 degree roll followed by a simulated roof-to-ground impact. Recognizing the unpredictability of the real world rollover phenomenon, this test provides a repeatable and consistent dynamic environment for suitable lab evaluation. Similar NHTSA research during the mid-1990s demonstrated an excursion reduction of up to 75% when an inflatable belt was compared to the standard three-point belt with a 50th percentile male [Rains, 1998].

Technologies being considered include integrated seat systems, pyrotechnic and electric resetable pretensioners, four-point belt systems, and inflatable belts. High speed video data are collected and analyzed to examine occupant head excursion throughout the tests and are presented for discussion. Though repeatable, concern about the real world relevancy of the RRT dynamics have been focused toward the absence of a mechanical component for lateral motion. This component is not inbuilt to the test fixture.

This research attempts to determine if reasonably reduced excursion is possible in the simulated rollover. This research has been constrained to examining restraint systems focused to the seat. Future research to include a partial vehicle cab structure is planned to allow evaluation of devices that utilize it for a reaction surface;​ such as rollover air bags.

Restraint advancements have primarily been focused on frontal and side crash performance. It is believed that many of these advancements can also aid in reducing occupant excursion during a rollover crash. Improving restraint effectiveness in rollovers may further enhance protection for belted, non-ejected occupants in rollovers.