Guidance-oriented advanced curve speed warning system in a connected vehicle environment

Area of Science:

• Road Safety
• Human-Computer Interaction
• Transportation Engineering

Background:

• Existing highway curve warning systems often fail to ensure driver speed compliance throughout the entire curve.
• Drivers may adjust speed before entering a curve but often exceed safe speeds within it.
• There is a need for advanced systems that provide continuous guidance during curve navigation.

Purpose of the Study:

• To develop and evaluate a guidance-oriented Advanced Curve Speed Warning (Advanced-CSW) system.
• To improve driver speed compliance on horizontal curves using real-time, in-vehicle messaging.
• To assess the system's effectiveness across various geometric, roadway, and traffic conditions.

Main Methods:

• Developed an Advanced-CSW system utilizing Dedicated Short-Range Communication (DSRC) for vehicle-infrastructure (V2I) communication.
• Conducted a driving simulator experiment with 30 participants navigating curves under diverse conditions (severity, illumination, wetness).
• Evaluated system performance by measuring speed difference (in-curve mean speed vs. advisory speed) and comparing with existing systems (CSW, CSO).

Main Results:

• Male drivers showed significantly increased speed compliance with continuous, guided messages compared to one-time warnings or signs.
• Female drivers improved compliance using curve signs only, outperforming one-time warnings or continuous guided messages.
• Male drivers using Advanced-CSW reduced speed differences by 6.53–7.68 mi/h compared to other systems.

Conclusions:

• The Advanced-CSW system effectively enhances driver speed compliance on horizontal curves, particularly for male drivers.
• Continuous, adaptive speed guidance throughout the curve navigation is superior to traditional warning methods.
• The system offers a promising direction for designing more effective curve warning systems adaptable to real-time conditions.