Transportation Human Factors 

About: Transportation Human Factors is an academic journal. The journal publishes majorly in the area(s): Poison control & Driving simulator. It has an ISSN identifier of 1093-9741. Over the lifetime, 64 publications have been published receiving 2083 citations.

"How Long Does It Take to Stop?" Methodological Analysis of Driver Perception-Brake Times

Abstract: Human perception-brake reaction time (RT) studies have reported a wide variety of results. By analyzing a large number of data sets, however, it is possible to estimate times under specific conditions. The most important variable is driver expectation, which affects RTs by a factor of 2. When fully aware of the time and location of the brake signal, drivers can detect a signal and move the foot from accelerator to brake pedal in about 0.70 to 0.75 sec. Response to unexpected, but common signals, such as a lead car's brake lights, is about 1.25 sec, whereas RTs for surprise events, such as an object suddenly moving into the driver's path, is roughly 1.5 sec. These times are modulated somewhat by other factors, including driver age and gender, cognitive load, and urgency.

Brake reaction times and driver behavior analysis

Abstract: In his review on driver brake reaction times (RTs), Green (2000) rightly criticizes attempts to seek a canonical brake RT, and proposes to determine expected brake RT for specific situations. However, based on his analysis, he presents a series of values for expected, unexpected, and surprise situations that appear to generalize over a variety of different driver tasks and traffic situations without sufficient concern for urgency or criticality of the situations. This sampling problem may lead easily to biased and somewhat arbitrary estimates. Thus, instead of 1.25 sec for "unexpected" situations, the median yellow response time for the critical conditions (at short time-to-stop-line) is rather below 1.0 sec, and instead of 1.5 sec mean brake RT for surprise situations, available on-road data suggest that in fairly urgent situations-at time-to-collision of about 4.0 sec-unalerted drivers are able to react to an obstacle by braking at an average latency of 1.0 to 1.3 sec, depending on site. More emphasis s...

Driver behavior in an emergency situation in the Automated Highway System

Abstract: Twenty participants completed test rides in a normal and an Automated Highway System (AHS) vehicle in a driving simulator. Three AHS conditions were tested: driving in a platoon of cars at 1 sec and at 0.25 sec time headway and driving as a platoon leader. Of particular interest was overreliance on the automated system, which was tested in an emergency condition where the automated system failed to function properly and the driver actively had to take over speed control to avoid an uncomfortable short headway of 0.1 m. In all conditions driver behavior and heart rate were registered, and ratings of activation, workload, safety, risk, and acceptance of the AHS were collected after the test rides. Results show lower physiological and subjectively experienced levels of activation and mental effort in conditions of automated driving. In the emergency situation, only half of the participants took over control, which supports the idea that AHS, as any automation, is susceptible to complacency. This condition re...

Using Cellular Telephones in Vehicles: Safe or Unsafe?

Abstract: Cellular telephones are commonplace among the general driving public, and concerns have been raised about the safety implications of their use while driving. In response to these concerns, the National Highway Traffic Safety Administration (NHTSA) initiated a comprehensive data- and information-gathering effort to help ensure that the public, the wireless industry, and the states have sufficient knowledge upon which to make informed decisions regarding the issues, to identify needed initiatives and research, and to explore the broader safety issues associated with use of these systems. The topic was explored by reviewing available data and information on user characteristics, examining crash statistics, performing statistical analyses, conducting a comprehensive critical review of relevant published research studies, examining human factors design issues, and identifying a set of future research needs. Findings indicate a lack of systematic crash data collection that would help characterize cellular-telep...

Workload and Reliability of Predictor Displays in Aircraft Traffic Avoidance

Abstract: In 2 experiments we describe the relevance of aircraft predictor information to the availability and deployment of visual attention. In both, airplane pilots fly a simulator in which flight path prediction is given bearing on the future state of their own aircraft and of a second traffic "intruder" aircraft that they must maneuver to avoid. The cockpit traffic display on which this information is depicted is an integral component of the concept of free flight or pilot self-separation. In Experiment 1 we show that added layers of predictive information improve performance, reduce mental workload (as subjectively measured), and that added complexity of the visual display thus resulting does not increase the inferred measure of head downtime (secondary-task performance). In Experiment 2 we examine the consequences to performance and visual attention if prediction is occasionally in error. We adopt the hypothesis that trust is related to the relative allocation of attention between the predictor symbol and the raw data of actual aircraft state. Such unreliability damages performance to some extent, particularly when the unreliable predictor forecasts more complex conflict geometry. This cost reveals the substantial allocation of attention to the predictor symbol. However, pilots, knowing the level of unreliability, appear to be relatively well calibrated in their allocation of attention between the 2 information sources.