Knowledge Resources

This paper describes the potential of in-vehicle data recorder (IVDR) systems to be used in commercial and research applications as tools to monitor and provide feedback to drivers on their on-road behavior. The implementation of IVDR was demonstrated using the example of the DriveDiagnostics system. This system can identify various maneuver types that occur in the raw measurements, and use this information to calculate risk indices that indicate on the overall trip safety. Drivers received feedback through various summary reports, real-time text messages or an in-vehicle display unit. Validation tests with the system demonstrated promising potential as a measurement tool to evaluate driving behavior. Reductions in crash rates and the risk indices were observed in the short-term.

Methodology
The implementation of the IVDR included two stages:

• Blind-profiling, where the drivers were informed that an IVDR was installed as a safety-related system but with no feedback about their driving. They were informed that the information collected by the system would not be used by their managers. It was expected that the installation had minimal effect on drivers' behavior during this period.
• Feedback stage - At the end of the blind-profiling, the drivers were informed about the IVDR system and the feedback it provides. They received initial feedback on their driving, and received access to a web site with their driving data compared to fleet averages. Drivers were informed that the IVDR record would not be used against them.

Feedback included green (good), yellow (questionable), and red (bad) visual displays to give commercial drivers feedback on their driving safety. Drivers could see their performance indicators in real-time while driving and via a secure web link after driving. Driving risk was assessed based on vehicle speeds, lateral accelerations (e.g., on curves), and longitudinal accelerations (e.g., hard braking).

Findings
The results show a statistically significant reduction of 38 percent in crash rates, but not in fault crash rates, which were only reduced by 5 percent. Some of the reduction in overall crash rates may be attributed to a general decrease in crashes in the company fleet - a 19 percent reduction occurred during the period studied. The small reduction in fault crash rates may be a result of the small number of fault crashes in the sample.

Risk indices were calculated for the blind-profiling period and for seven months after exposure to the IVDR feedback. Comparison of these indices show a reduction in the mean risk index of 33 percent after initial exposure to the IVDR feedback. The risk indices remained at similar levels during the entire seven months after exposure. Additional analysis showed that risk indices could be reduced further if the drivers continue to access the IVDR feedback.

Conclusion
IVDR data is a reliable source of driving behavior and vehicle usage data. It is recommended for use by fleet safety managers, licensing authorities and parents of young drivers, insurance companies, and road authorities.