Host: Fujie Zhou, Texas Transportation Institute
When: Tuesday, February 18th, 2020 | 4 PM Eastern Time
Webinar Link: https://virginiatech.zoom.us/j/856247499z
Deployment of automated vehicles (AVs) has many benefits, such as reduction of congestion and traffic accidents, increased lane capacity, lower fuel consumption, increased transport accessibility, and reduced travel time and transportation costs. However, one aspect of AVs that is worthy of notable attention is their impact on risk of roadway hydroplaning and pavement life. Since most AVs are programmed to follow a set path and maintain a lateral position in the center of the lane, over time, significant pavement rutting will occur. This study directly measured AV lateral wandering patterns and then compared with human driven vehicles. It was found that wandering patterns of both AVs and human driven vehicles could be modeled with a normal distribution but have significantly different standard deviations. AVs wander laterally at least 3 times smaller than regular human driven vehicles. The influence of AVs (all AVs or mixed with regular human driven vehicles) on pavement rutting and fatigue life was analyzed with the Texas Mechanistic-Empirical Flexible Pavement Design System (TxME). The researchers discovered that the AVs with smaller lateral wandering would shorten pavement fatigue life by 22 percent. Meanwhile, pavement rut depth increases by 30 percent which leads to a much higher risk for AVs hydroplaning. The researchers also calculated the maximum tolerable rut depths at different hydroplaning speeds. It is noted that the AVs have a much smaller tolerable rut depth than the regular human driven vehicles due to greater water film thickness in the rutted wheel paths. To reduce the negative impact of AVs on roadway safety and pavement life, this research recommends an optimal AV wandering pattern: a uniform distribution. Not only does the uniform distribution eliminate the negative effect of AVs, but more importantly, it results in prolonged pavement life and decreased hydroplaning potential.
This webinar features research from Safe-D Project 02-008: Pavement Perspective on AV Safety through Optimizing Lateral Positioning Pattern
Host: Russell H. Henk, P.E., Program Manager & Senior Research Engineer, Center for Transportation Safety (CTS) – Youth Transportation Safety Program (YTS)
When: Tuesday, February 25th, 2020 | 4 PM Eastern Time
Webinar Link: https://virginiatech.zoom.us/j/963542171
Traffic crashes continue to be the leading cause of unintentional death and injury of youth across the United States. New and innovative interventions continue to be developed to address this public health issue for this high-risk driving population. This webinar will provide a variety of data associated with an incentive-based smartphone app developed by the Texas A&M Transportation Institute as part of the peer-to-peer safe driving program, Teens in the Driver Seat®. One of the core features of the app involves a reward system in which drivers earn points for miles driven without any phone interaction. The points can be redeemed for rewards and as a basis for competitions and achievement of safe driving levels. This project examined data collected from two distinct smartphone app deployments over the timespan of several months each – one in 2017 and one in 2018. The datasets include over 12,200 trips and more than 100,000 miles logged using the app. Statistical analyses were performed to assess the influence of incentives on the frequency of distracted driving. Statistically significant reductions in distracted driving (at the 95 percent confidence level) were shown to have occurred when incentives were awarded for distraction-free driving. Several other data of interest are presented herein as well. Topics discussed will also include lessons learned regarding the pros and cons of smartphone app deployment of this nature.
This webinar features research from Safe-D Project TTI-01-01: Analysis of an Incentive-Based Smartphone App for Young Drivers