Motorist Understanding of Pavement Centre Lines and their Effect on Driving Behaviour

Human factors and more generally driver errors account for the largest number of road accidents. Driver errors are external human factors that can contribute to specific error types selected from slip, lapse, mistake and violation. Action and information retrieval errors are both examples of driver errors. The failure to interpret correctly an intended road marking’s message causes driver misunderstanding and lead to a driver error. Centre lines are examples of such markings and if misread or unrecognised may cause unintentional driver violations and unsafe driving. This study focused on the examining of driver understanding of road markings, and the influence of centre lines on their driving behaviour. This study determined that drivers had a much better understanding of the overtaking messages intended by road markings, than the directional flow message. Drivers demonstrated that they relied more on signs and other drivers to determine whether the road is a two-way or not. This study demonstrated that the presence of both centre lines and edge lines have a positive effect on a driver in handling and controlling of their vehicles’ position. It was postulated from this study that the absence of the edge lines has a more significant effect on a vehicle’s position than the absence of centre lines.

Impacts on Driver Perceptions in Initial Exposure to ADAS Technologies

Advanced driver assistance systems (ADAS) offer great promise in improving the safety of our roadways. Although ADAS have rapidly entered the U.S. passenger vehicle market, little is known about driver understanding and attitudes toward ADAS, especially the impact of their initial exposure to the technologies. Whereas some ADAS may be easy to learn and use, others are more complex and have limitations that may not be obvious to the driver. The Technology Demonstration Study was conducted to evaluate how the ways in which drivers learn about ADAS affect their knowledge and perceptions of the technology. Two base learning methods were utilized for the study, both of which are traditional forms of learning for the average driver: reading the owner’s manual and making observations inside the vehicle. From these base learning methods, four learning protocols were developed, two of which included both methods. This paper investigates how drivers’ perceptions of usefulness, apprehension, and trust with regard to ADAS functionality were affected by initial exposure to the technology. Participants who observed ADAS during a demonstration drive had more positive perceptions relative to those who only read about them, particularly for ADAS that provide vehicle control.

A comparative evaluation of the impact of average speed enforcement (ASE) on passenger and minibus taxi vehicle drivers on the R61 in South Africa

Average Speed Enforcement (ASE) is an emergent alternative to instantaneous speed limit enforcement to improve road safety, and is used to enforce an average speed limit over a road segment. This paper presents a study on the response of passenger vehicles and minibus taxis to ASE on the R61 in South Africa. A spatio-temporal quantitative study of speed compliance is conducted, where metrics such as speed variability, average speed and 85th percentile speed measured prior to, and during enforcement are analysed for two prominent modes of transport – passenger vehicles and minibus taxis. These measurements are taken on the enforcement route and on control routes adjacent to and further away from the enforcement route. A qualitative study is also conducted to evaluate the relationship between speed compliance and driver understanding of the system. The impact of the system on crash risk and injury severity is also examined before and during enforcement. For passenger vehicles, results show that the introduction of ASE was followed by a reduction in mean speed on the enforcement route and adjacent control route. For minibus taxis, it was found that ASE appears to have little influence on improving speed compliance, which is likely associated with a lack of driver understanding on how the system operates.

Influence of Remotely Operated Stop–Slow Controls on Driver Behavior in Work Zones

Remotely operated devices for traffic control—portable traffic lights and automated flagger assistance devices—are used to improve flagger safety in a one-lane-each-way work zone with lane closure. Previous research has measured the effectiveness of these devices as driver compliance rates and driver understanding of the devices, but the effects of these devices on driver behavior have not yet been examined comprehensively. Therefore, the influence of remotely operated stop–slow traffic control devices on driver behavior was examined. Video-recorded traffic movements from a rural work zone in the Queensland state of Australia provided driver speeds, deceleration profiles, stopping behavior, and compliance rates for a set of remotely operated devices new to Australia: static red–amber–green lights, static red–amber lights, static red–amber arrow lights, and mechanical stop–slow signs. Pneumatic tube traffic counters were used to collect driver speeds before and after the devices, and an on-road driver survey was conducted to elicit driver understanding of the devices. Results indicated that drivers had difficulty understanding the new devices, particularly the amber light and amber arrow options (which confused drivers about their meaning—to stop or to go). The new remotely operated devices resulted in higher approach speeds, greater variability in approach speeds, and faster deceleration rates than the flagger method. The good compliance rates observed with the remotely operated devices imply that the devices could improve flagger safety by reducing flagger exposure to traffic; however, the negative effects on driver behavior might indicate an increased risk of rear-end crashes in the advance warning area.

Driver Understanding of Pavement Marking Colors and Patterns

Driver understanding of the current U.S. system of yellow–white pavement markings was assessed through a driver survey. The survey was used to evaluate drivers’ ability to describe the pavement marking color code, drivers’ reliance on pavement marking patterns when interpreting marking messages, and drivers’ reliance on pavement marking color when interpreting marking messages. Researchers surveyed 851 drivers in 5 states, with respondents representing 47 states, the District of Columbia, and Puerto Rico. The survey results indicate that drivers tend to use signs and other traffic as the primary cue to determine whether a road is one-way or two-way. A substantial proportion of respondents had an understanding of the use of marking color to differentiate between one-way and two-way roads, but this knowledge is not the primary tool that drivers use to distinguish the direction of travel on a road. Approximately 75% of the drivers surveyed understood the basic concept that a single broken yellow line separates opposing traffic on a two-lane road. The presence of a solid line (either double solid or solid and broken) in the centerline increases comprehension of directional flow to approximately 85%; more than 90% of the drivers surveyed understood that a solid line (either double solid or solid and broken) prohibits passing. Almost 95% of drivers indicated that passing is permitted with a broken line. The survey results indicate that the yellow–white pavement marking system is better understood than previously believed.