Analysis of a Frontal Impact of a Formula SAE Vehicle

David Rising, Kettering University
Jason Kane, Kettering University
Nick Vernon, Kettering University
Joseph Adkins, Kettering University
Craig Hoff, Kettering University
Janet Brelim-Fornari, Kettering University

Abstract

The objective of this study was to determine risk of injury to the driver during a frontal impact in a Formula SAE vehicle. Formula SAE is a collegiate student design competition where every year universities worldwide build and compete with open-wheel formula-style race cars. Formula SAE 2006 rules stipulate the use of an impact attenuator to absorb energy in the event of a frontal impact. These rules mandated an average deceleration not to exceed 20-g from a speed of 7.0 m/s (23 ft/s), but do not specify a specific time or pulse shape of the deceleration. The pulse shapes tested in this study included an early high-g, constant-g, and late high-g pulse. The tests were performed using the deceleration sled at the Kettering University Crash Safety Center. Using industry standard practices, this study examined the driver’s risk of injury with regard to neck and femur loads, head and chest accelerations, as well as kinematic analysis using high speed video. The tests were repeated with and without the use of a HANS device. HIC and Nij criteria are presented and compared for the various impact pulses to examine the severity of each pulse. Results are compared with passenger vehicle safety criteria and race vehicle safety criteria. Conclusions are drawn regarding the necessity of a HANS device, as well as determining the best practice for design of the impact attenuator, driver compartment, and headrest.

The objective of this study was to determine risk of injury to the driver during a frontal impact in a Formula SAE vehicle. Formula SAE is a collegiate student design competition where every year universities worldwide build and compete with open-wheel formula-style race cars. Formula SAE 2006 rules stipulate the use of an impact attenuator to absorb energy in the event of a frontal impact. These rules mandated an average deceleration not to exceed 20-g from a speed of 7.0 m/s (23 ft/s), but do not specify a specific time or pulse shape of the deceleration. The pulse shapes tested in this study included an early high-g, constant-g, and late high-g pulse. The tests were performed using the deceleration sled at the Kettering University Crash Safety Center. Using industry standard practices, this study examined the driver’s risk of injury with regard to neck and femur loads, head and chest accelerations, as well as kinematic analysis using high speed video. The tests were repeated with and without the use of a HANS device. HIC and Nij criteria are presented and compared for the various impact pulses to examine the severity of each pulse. Results are compared with passenger vehicle safety criteria and race vehicle safety criteria. Conclusions are drawn regarding the necessity of a HANS device, as well as determining the best practice for design of the impact attenuator, driver compartment, and headrest.