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Electronic stability control (ESC) systems have been the subject of statistical analyses of road accidents, testing by NHTSA and others, and Federal Motor Vehicle Safety Standard 126. ESC systems employ complex algorithms to process information from multiple sensors and intervene to improve vehicle directional control. They are called upon to function under conditions of varying tire-road friction coefficients, grades, vehicle loads, and driver inputs. In this study, Engineering Dynamics Corporation SIMON modeling software was used to examine simulated vehicle responses due to single-wheel braking (as utilized by ESC systems) when subjected to a variety of factors. The stabilizing force due to single-wheel braking was found to be sensitive to laterally split friction coefficient conditions, braking, and other specific driver inputs. ESC systems are likely to be subject to similar limitations.

Analyses were performed using field data for belted drivers of light vehicles in frontal crashes to examine the frequency and severity of frontal crashes with narrow objects. This study examined the distribution of injuries by body region, crash severity, and single- versus multiple-vehicle crashes for narrow object and all other crashes. Factors influencing injuries in different types of frontal crashes were identified, and risk of injury to belted drivers in narrow object crashes versus other frontal crashes was examined. A detailed review of about 400 NASS cases involving narrow object crashes was also performed. Results indicate frontal crashes involving impact with poles, posts, or trees are relatively infrequent. Overall, the fatal risk for belted drivers is lower in narrow object crashes than in other types of frontal crashes.

Field data is used to evaluate the number of light vehicle occupants injured or killed in side underride crashes with “combination trucks”. Statistical analyses were performed of federal crash data files for side underride crashes with passenger compartment intrusion (PCI) in the light vehicle, and an in-depth review of combination truck crashes was performed using photographs, scene diagrams, and other vehicle and occupant data. Results show that, annually, fewer than 4% of all occupant fatalities and approximately 5.5% of all occupant injuries sustained in light vehicles that have collided with combination trucks can be attributed to side impact underride with PCI.

Studies used 1981–2006 FARS and state crash data to examine the relative importance of vehicular, driver, and environmental factors in influencing odds of driver fatality in two-vehicle (car-to-car, light truck-to-car, and light truck-to-light truck) frontal crashes for 1981–2003 model-year vehicles. It was found that all vehicle factors, including vehicle frontal stiffness, have a second order effect compared to vehicle weight. Most of the driver factors included were found to be highly significant. Assumptions and methodology used by other vehicle size/weight safety studies were also evaluated. Results show trends similar to those of other key studies, with one notable exception.