Crash barriers and driver behavior: a simulator study.

Area of Science:

• Road safety engineering
• Human factors in transportation
• Traffic psychology

Background:

• Roadside safety features, such as W-beam guardrails, are crucial for mitigating crash severity.
• Understanding driver perception and behavior in response to road design is essential for optimizing safety.
• Previous research has explored the impact of road geometry on driving, but the combined effect of road width and roadside barriers requires further investigation.

Purpose of the Study:

• To investigate driver experience, including stress, feelings, and driving patterns, when encountering W-beam guardrails on narrow versus wider roads.
• To compare subjective driver perceptions with objective driving data (speed, lateral position) and physiological stress indicators (heart rate variability).
• To evaluate the utility of driving simulators and questionnaires in assessing driver responses to road features.

Main Methods:

• Utilized the VTI Driving Simulator III to record speed and lateral vehicle position.
• Collected electrocardiogram (ECG) data to measure heart rate variability (HRV) as an indicator of stress.
• Employed oral and written questionnaires to capture subjective driver experiences and perceptions.

Main Results:

• Driving speeds were slightly higher on wider roads and roads with guardrails.
• Drivers maintained a position closer to the road center on narrower roads and roads with guardrails.
• Heart rate variability data did not show increased stress related to road width or guardrails; however, written feedback indicated higher speeds on wider roads.

Conclusions:

• Increased speed on roads with guardrails may be attributed to drivers' enhanced sense of security.
• An experimental design combining simulator data and questionnaire feedback is effective for studying driver responses.
• Driving simulators are valuable tools for evaluating road features like guardrails and potentially other elements such as lighting and signage.