Research Progress & Insights

Track 1: Define Problems by Identifying Types of Distractions

Research Accomplishments

• Analyzed 2005 to 2007 data from the National Motor Vehicle Crash Causation Survey (NMVCCS) database, which consists of on-scene, in-depth multidisciplinary investigations of crashes. This approach provided more details than typical police reports about driver, vehicle, and traffic characteristics associated with distraction- related crashes.

• Completed a naturalistic study, conducted by Virginia Tech Transportation Institute, in which 100 cars in Northern Virginia were instrumented.
• Completed a naturalistic study examining driver performance and distraction with hand-held, portable hands-free, and integrated (built-in) hands-free configurations.

• Completed an assessment of international best practices in data collection methods and improvements in police reporting to reduce the variability (due to poor recall, avoiding self-incrimination or admission of fault) in reporting on distraction. Assessment relates improved reporting to the level of training and reporting requirements.

Critical Research Insights

• The NMVCCS data indicate that distractions internal to the vehicle were a critical reason in about 11 percent of crashes studied. An analysis of the types of internal distractions found that about 0.2 percent of drivers were dialing or hanging up phones, about 0.9 percent were adjusting radios/CDs or other controls, and about 12 percent were conversing with passengers or on cell phones. Drivers 16 to 25 years old had the highest rate (6.6 percent) of being engaged in at least one interior non-driving activity.

• Analyses of the 100-Car Study recorded video data allowed researchers to determine whether the drivers were distracted in the moments leading up to the crashes or near-crashes. The researchers also analyzed video clips in which the drivers were engaging in secondary tasks. Comparing distractions during normal driving to distractions during crashes and near-crashes, estimates were made of the relative risk of drivers when distracted. Due to the success of this method, the Transportation Research Board, under its Strategic Highway Research Program 2 (SHRP2), has initiated a much larger naturalistic driving study with a wider sample of drivers, which is expected to be more representative of the general driving public.
• Analyses of the naturalistic cell phone study data corroborated earlier findings in the 100-Car Study that visual-manual interactions with cell phones (or other devices and tasks) are associated with the highest levels of increased crash and near-crash risk.

• Improved training and standards for coding distraction on police accident reports would help NHTSA and the states to better estimate distracted- driving-related events and to monitor any new trends and the effects of countermeasures.

Next Steps

• The NMVCCS analysis has helped to define the distraction problem; with completion of this task, results are informing Track 2 activities on defining current and best practices.

• The SHRP2 analysis also helped to define the distraction problem; and have also informed Track 2 activities, which will ultimately be used to support the Human Factors for Connected Vehicles guidelines related to distraction, specifically identifying countermeasures, such as standards to lock out distracting device operation, and recommendations restricting driver use of distracting devices.

Track 2: Develop and Evaluate Performance Metrics for Distraction Mitigation

Research Accomplishments

• The US DOT has identified the state-of-the-industry in distraction mitigation. Analysis has resulted in preliminary recommendations on best practices for performance metrics. This set of preliminary recommendations will form the basis for future efforts to develop design guidance and assessment tools.

• The US DOT also published its Phase 1 Visual-Manual NHTSA Driver Distraction Guidelines For In-Vehicle Electronic Devices in 2013. NHTSA is currently working on its Phase 2 Distraction Guidelines, which will apply to visual-manual interfaces for portable and aftermarket devices.

Critical Research Insights

• A long-standing challenge in human factors research is how to measure driver distraction. Distraction is significantly correlated to driver behavior, which is difficult to measure. To address this challenge, a wide and inconsistent range of definitions and different measurement techniques have been developed by researchers, academia, and industry.

• In reviewing and identifying best practices, NHTSA is on the leading edge of codifying a set of consistent practices for measuring and assessing driver distraction. These practices will be instrumental in producing a set of connected vehicle distracted driver guidelines, which will be consistent with NHTSA’s overarching policies and guidelines on distracted driving.

Next Steps

• Integrate DVI design guidance and distraction assessment research generated since 2011 into human factors design principles product.

• Continue the development of DVI guidance with a focus on non-safety applications and connectivity issues. This activity will focus on design guidance gaps for DVIs associated with light vehicles, heavy vehicles, and transit operators; all age groups; and V2I interfaces.
• Conduct additional research identifying specific warning characteristics for Connected Vehicle safety applications that help to optimize effectiveness of those warnings.

Track 3: Produce an Integration Strategy

Research Accomplishments

• The US DOT completed DVI Design Criteria in March 2011. These criteria were delivered to the Safety Pilot developers and will be used as a starting point for further DVI design research, which will ultimately inform the final HFCV Guidelines.

• To develop an integration strategy, the US DOT has finalized a Requirements Definition Final Report and a Guidelines Framework (both completed in June 2011).
• The US DOT completed the Integration Architecture product that describes a system approach for filtering, prioritizing, and scheduling the presentation of various messages enabled through the Connected Vehicle environment. This Integration Architecture is part of the DVI Design Principles product that will be published in 2015.

• The US DOT is currently developing an integrated ConOps and an overall “Metric Toolbox” for evaluating multiple, integrated DVI-based connected vehicle systems and applications, including safety and non-safety applications, validation efforts, light vehicles, heavy vehicles, transit operators, all age groups, and V2I issues.

Critical Research Insights

• Research has highlighted the criticality of producing further data and insights as a means of helping to define how multiple DVIs can be integrated so that the driver perceives a single system rather than being bombarded with various messages without coordination. The results suggest that integrating and coordinating information from multiple sources is important to driving performance with respect to the volume and rate of information, the type and complexity of the information, the priority of the information, and physical characteristics of the information displays.

Next Steps

• Validate integration concepts and incorporate into the Human Factors Design Principles for the integration of connected vehicle information, how to prioritize that information, and how to best present the information to the driver without distraction or unintended consequences. These design principles are the primary product of this program.

• Continue to develop the predictive DVI evaluation tool for validation and refinement. This is a software tool for designers to be able to estimate distraction potential or workload issues for their DVI and system configurations.

Track 4: Develop Longer-Term Exposure Testing

Research Accomplishments

• NHTSA has developed an experimental design, implementation plan, and test requirements for launching a field operational experiment that will test instrumented vehicles with advanced collision warning systems and measure driver behavior over time. This first test will deliver insights into how drivers change their behavior or responses to safety devices and will assess longer-term impacts over time. The test is being conducted on forward collision warning applications. An initial statement of work, released in 2011, did not result in an award due to critical questions by industry. With further clarification, a second statement of work is expected to be released in the spring of 2012.

Critical Research Insights

• Data collection concluded in September 2014.

Next Steps

• Conduct the analyses to identify driver response changes to forward collision warnings over time.

Track 5: Perform Strategic Outreach with Stakeholders

Research Accomplishments

• The US DOT hosted a public meeting to give an overview of research under the Human Factors for Connected Vehicles Program, including V2V and V2I communication, heavy-truck-related research, and environmental research related to connected vehicles. DOT representatives led a discussion to facilitate the exchange of ideas with stakeholders.

Critical Research Insights

• Stakeholders confirmed that the US DOT is addressing the right issues for connected vehicles. Input helped to further define gaps that need to be addressed and which inform the current program and future projects.

• Stakeholders provided feedback on outlines and early drafts of the Human Factors Design Principles for connected vehicles. Input helped to ensure the Design Principles meet stakeholder needs and result in a most useful product for system developers.

Next Steps

• NHTSA is planning to hold another workshop in 2014 to present results and receive additional stakeholder feedback on the design principles.