Fifty-five (55) Drivers Participated in 20 Different Scenarios to Study Impacts of CAV Technologies on Driver Behavior Near Work Zones.
Maryland, United States
Comprehensive Study on CMV Safety Using ITS in Work Zones on Freeways and Arterials
Summary Information
Commercial Motor Vehicles (CMVs) have seen safety challenges in work zones due to their larger size, weight, and blind spots compared to passenger vehicles. Intelligent Transportation Systems (ITS) technologies, such as Variable Speed Limits (VSL) and Dynamic Message Signs (DMS), offer real-time information and instructions to drivers, helping them anticipate and adapt to changes in the roadway ahead. Furthermore, Connected and Automated Vehicle (CAV) technologies can be used to enhance safety directly at the vehicle level. This study focused on assessing the impact of these varied warning strategies on CMV driver behavior in work zones with 55 drivers using a driver simulator, in which drivers drove more than three miles along I-95 interstate highway. By conducting experiments in Maryland, this study compared the effectiveness of traditional static work zone signage, ITS warning devices, and CAV technologies to assess the effectiveness in awareness of work zones.
METHODOLOGY
This study designed three simulated work zones to mimic real-life conditions on or near I-95 in Maryland: one with an arterial lane closure, one with a freeway lane closure, and one with two freeway lanes closed. Researchers tested driver responses under various environmental settings (clear, foggy, rainy; mild or heavy traffic; day or night) and with different levels of safety technology alerts (none, static warning signs, ITS technologies, and CAV technologies), creating 20 unique scenarios. CAV technologies include CAV warnings, automated driving voluntarily (similar to Level 3 automation), and automated driving involuntary (vehicle automatically takes control without asking the driver's permission). Data on driving behaviors like speed, braking, throttle use, eye gaze frequency and duration, and lateral movement were collected, specifically for sign locations and work zone start/end points. Additionally, pre- and post-experiment surveys collected socio-economic data, prior knowledge of CAV technology, and feedback on its perceived effectiveness.
FINDINGS
- The survey revealed that 56 percent of the participants considered these features to be beneficial for safe driving. Likewise, 67 percent believed that the CAV function in particular would serve as a valuable asset for enhancing driving safety.
- Comparing the ITS scenario to the static work zone warning scenario under dry weather and heavy traffic in daytime, participants in the ITS scenario under the same traffic situation had 22 percent more in their safety distance to roadside as approaching to the work zone. This result indicated that drivers drove smoother as they were aware of the upcoming work zone.
