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Run off road events are frequent and can result in severe consequences. The reasons for leaving the road are numerous and the sequence the car is exerted to differs in most events. The objective of this study is to identify different situations and mechanisms both in respect to accident avoidance and occupant protection and to present test methods addressing the different identified mechanisms of run off road occupant safety. Mechanisms and influencing factors are identified using statistical and in-depth crash data as well as driving data. There are a number of reasons for leaving the road; driver fatigue, driver distraction and inadequate speed in relation to the traffic situation to mention a few. An outline of principle test methods for evaluating technology assisting the driver to stay on the road is presented in relation to the identified situations and mechanisms. Crash test methods for some typical run off road scenarios are suggested.

Different types of driver workload are suggested to impact driving performance. Operating a vehicle in a situation where the driver feel uneasy is one example of driver workload. In this study, passenger car driving data collected with Naturalistic Driving Study (NDS) data acquisition equipment was analyzed, aiming to identify situations corresponding to a high driver's subjective rating of ‘unease’. Data from an experimental study with subjects driving a passenger car in normal traffic was used. Situations were rated by the subjects according to experienced ‘unease’, and the Controller Area Network (CAN) data from the vehicle was used to describe the driving conditions and identify driving patterns corresponding to the situations rated as ‘uneasy’. These driving patterns were matched with the data in a NDS database and the method was validated using video data. Two data mining approaches were applied.

NHTSA recently proposed performance guidelines for visual-manual interaction with non-driving related in-vehicle systems. While a commendable effort to reduce distraction related crashes, in part they seem overly strict. In particular, NHTSA proposes that for each driver performing a secondary task, no more than15 % of the off-road eye glances can be longer than 2.0 s, and 21 in 24 drivers must meet this criterion. The applicability of this criterion was assessed in a study using data from two eye-tracker based studies, involving 35 subjects performing a range of secondary tasks on normal roads. Results showed that over tasks, the average off-road glance duration lengths were quite robust within drivers but varied widely between drivers. Off-road glance duration length thus seems more to reflect individual driver attention allocation strategy than in-vehicle task complexity. Also, several drivers failed to meet the suggested criterion.

The Inflatable Curtain (IC) has shown great potential to reduce head injuries in side impacts. This study explores and presents enhanced performance in two steps of improved activation algorithms. Crash data analysis, 21 full scale crash tests and component tests in a custom built drop tower rig have been performed. The IC performance in wider crash scenarios, including side impacts outside the occupant compartment (L-type impacts), was evaluated. Both statistical crash data and in-depth studies were used. It was found in the analysis of real life crashes that moderate to fatal head injuries can occur without intrusion in the occupant compartment. In L-type side impacts, the motion of the occupant relative to the vehicle interior may cause a head impact of sufficiently high severity to cause moderate to severe head injuries. A combined analysis of real world crash data and crash test results indicates that a substantial reduction in moderate to fatal head injuries can be achieved.