Vehicle Inversion Demonstrations

Exponent uses vehicle inversion systems to conduct simulations of vehicle rollovers. The various systems we use for our client investigations include: 

Indoor Quasi-Static Vehicle Inversion Demonstration Fixture

The indoor quasi-static vehicle inversion fixture provides a means to conduct full-scale quasi-static simulations of virtually any vehicle rollover. The fixture can accommodate most passenger vehicles, and vehicles can be secured in the fixture in orientations that represent pitch or yaw rotation. Anthropomorphic Test Devices (ATDs) or human subjects are used in these simulations and are seated and restrained in one of the vehicle’s seating locations. The vehicle is slowly rolled to the desired inversion position where the parameter(s) of interest can be evaluated.

Exponent’s Institutional Review Board (IRB) plays an important role in verifying that appropriate steps are taken to protect the welfare of humans participating as subjects in these studies.  Subjects are screened for health or medical conditions that may be aggravated by participation.

Highlights of Exponent's indoor inversion demonstration fixture include: the ability to conduct ground-level surrogate studies followed by the inversion demonstration, easy evaluation of parameters such as restraint geometry and head clearance in an inverted position, an open design that allows unobstructed photography, quick vehicle change-out times, and a climate- and lighting-controlled environment.

Outdoor Quasi-Static Vehicle Inversion Demonstration Fixture 

Like the indoor quasi-static vehicle inversion fixture, the outdoor quasi-static vehicle inversion fixture provides a means to conduct full-scale quasi-static simulations of vehicle rollovers. The fixture can accommodate most passenger vehicles. It is conveniently positioned next to our outdoor crash rail and can be used to quickly invert vehicles following a crash test such as the post-impact inversion requirements of the test standard FMVSS 301. The ramp-loading feature allows for quick vehicle change-out times, permitting multiple vehicle inversions to be completed in a given day.

Fixed-Axis Dynamic Spin Fixture

The Dynamic Spin Fixture is a machine that can generate full-scale passenger vehicle occupant compartment roll rates in excess of, 1,000 degrees per second. This fixture has been very useful in the evaluation of ATD excursion, the posture of restrained ATDs with a variety of seat belt configurations and side curtain airbags in response to the centripetal accelerations induced by real-world accident roll rates.