Abstract: This invention is for a simple, dynamic test device and its use to assess a wheeled vehicle's dynamic performance leading to a rollover including such conditions as a curb tripped rollover, a vehicle's occupant restraint performance before and during the first roll, the motion of the vehicle's occupants before and during a rollover, and the vehicle's occupant protection performance in a rollover including its roof crush resistance. It does so by carrying a vehicle over a horizontal circular path at a speed sufficient that the centrifugal force on the vehicle will cause it to roll. The device provides unique, repeatable test conditions leading to a rollover as well as during the rollover. The device can also be used to test an object by subjecting it a high level of acceleration, force, and yawing motion about orthogonal vectors.