November 30, 2006


AVST stands for “advanced vehicle safety technologies,” a class of built-in vehicle features such as “safety alerts (e.g., forward collision warning systems (FCW), road departure warning (RDCW), lane departure warning (LDW), intersection collision warning), systems that provide crash warning(s) and automated control (e.g., FCW combined with automatic braking), and other driver assistance systems that can impact safety (e.g., adaptive cruise control (ACC), brake assist, backover safety systems, and automatic lane keeping).”

NHTSA has announced it will hold a one-day meeting of experts and others on January 25, 2007, to consider how drivers interact with such features, both for better and for worse. “Proper designs will allow drivers to achieve the optimum safety benefit, whereas poor designs can limit or extinguish any advantage. The purpose of this forum is to identify human factors research to help guide the development and deployment of AVST that can improve safety and minimize potential adverse effects.”

Issues listed for the meeting include:

Unintended Consequences, i.e., driver behaviors that “can undermine the potential effectiveness of the technologies. For example, drivers may not respond quickly enough to collision warnings if the system has false alarms or too many warnings. Even if the system is perfect, drivers may over-rely on the technology, increase their risk taking behaviors, and negate any potential safety benefits. Drivers may not understand the system’s limitations and trust the system to a point where the system cannot perform to their expectations. For example, some systems only work within specified speed ranges or other limits, but drivers may expect the systems to perform at all speeds and in all conditions.”

Design Characteristics, i.e., “the variability in the design of these technologies within and across different vehicle manufacturers. As drivers change between vehicles with new or unfamiliar AVST characteristics or CWS interfaces, …drivers may miss or not comprehend an auditory warning from System A because they are accustomed to the warning sound provided by System B.”

Driver-centered Design, i.e., “how variations in driver performance should be accommodated by system design. Driver performance can vary from person to person, from situation to situation, and from time to time. For example, as a group, older drivers have poorer eyesight, slower reaction times, and a decreased ability to perform multiple tasks simultaneously. Drivers may respond differently in heavy traffic versus light traffic. Tired drivers may behave differently than alert drivers. The intended benefits of AVST may not be achieved unless the systems are designed to accommodate a broad range of the variability in the characteristics of the driving population. The safety concern is that some drivers may not detect warnings, respond appropriately, or turn off systems that are perceived as annoying or useless.”

Integrating Multiple Systems, i.e., “integrated warnings from multiple systems. While integrated systems have the potential to prevent a large portion of crashes, they pose unique design issues (e.g., with what priority should the alarms be presented). The Department of Transportation (DOT) is conducting a large-scale field operational test called Integrated Vehicle-Based Safety Systems (IVBSS) to better understand and evaluate some aspects of warning integration. However, more discussion is needed to fully address this emerging issue as increasing numbers of AVST are brought into vehicles.”

Posted by MVHAP at November 30, 2006 07:50 PM