Do cyclists disregard ‘priority-to-the-right’ more often than motorists?
Image credit: unsplashThe integration of autonomous driving into mixed traffic environments poses unique challenges - particularly at unsignalized intersections, where communication and cooperation with human road users are essential.
This study addresses a critical research gap by investigating the adherence to the “priority-to-the-right” rule at an urban unsignalized intersection, comparing behavioral patterns of cyclists and motorists.
Study Design
Using stationary mounted cameras, a 12-day field observation was conducted at an urban T-intersection in Braunschweig, Germany.
The class, trajectory, and scenario of road users were identified.
In 202 interaction cases, vehicles from the right (ego, with priority) encountered vehicles or bicycles from the left (foe, without priority).
Analysis
The study examined how:
- Ego’s direction,
- Foe’s class and lateral position, and
- Relative arrival time
influenced the passing order, using descriptive statistics and logistic regression.
Key Findings
- Cyclists violated the “priority-to-the-right” rule more frequently than motorists.
- Road users with priority were more likely to yield when:
- turning right,
- arriving later at the intersection, or
- facing an opposing road user close to the lane center.
Conclusion
This study underscores the importance of implicit communication in mixed traffic.
It provides empirical benchmarks for designing human-like autonomous driving systems - systems capable of interpreting and responding to nuanced road-user interactions at unsignalized intersections.
