Vehicle crashes often involve rollover. A vehicle rollover is a complex, 3-dimensional event that is quite difficult to model successfully. As a result, crash investigators often make simplifying assumptions that compromise the quality of the information learned from the analysis. Advances in vehicle simulation modeling have greatly reduced the amount of work required to perform rollover simulations. Rollover simulation holds promise as a tool to learn more about crashes involving rollover. This paper describes how the EDVSM simulation model calculates 3-dimensional forces and moments on the sprung mass (i.e., body exterior) and how these forces and moments are integrated into the equations of motion. The paper also provides some examples of the use of rollover simulation. Finally, the paper addresses the practical and theoretical limitations of rollover simulation as a tool for routine reconstruction of on-road and off-road crashes.
VEHICLE ROLLOVER is a significant safety problem. According to the NHTSA, an average of 227,000 rollover crashes (i.e., crashes in which rollover was the first harmful event) occurred annually between the years 1992 and 1996. These crashes resulted in an average of 9063 fatalities and over 200,000 non-fatal injuries each year. Rollover is second only to frontal crashes in terms of severity [1]. However, it cannot be concluded from previous research that speed alone is the major factor causing rollover crashes. Because of the frequency of this crash mode, and because of the typical severity of the resulting crash injuries, understanding the cause of rollover crashes is a critical aspect of motor vehicle safety research. Better understanding can ultimately lead to the development of safer vehicles and highways, as well as lead to a more knowledgeable driver.
This paper describes procedures for investigating rollover crashes. A literature review is included to assess the current state of the art and findings of other researchers. The main component of the paper is an in-depth evaluation of the use of the EDVSM [2] vehicle simulation model for studying rollover crashes. The vehicle model assumptions are presented and evaluated. Several examples of the use of EDVSM are provided. Finally, limitations of the model for use in rollover simulation are explored.