Keep it Real: Investigating Driver-Cyclist Interaction in Real-World Traffic

Cyclists encounter drivers in many traffic scenarios; good communication is key to avoiding collisions. Little is known about everyday driver-cyclist interaction and communication. This is important in designing Automated Vehicles (AVs) that must drive safely around cyclists. We explored driver-cyclist interaction across diverse scenarios through in-the-wild observations (N = 414) and a naturalistic study involving cyclists wearing eye-trackers (N = 12). Results showed cyclists attended to road markings and traffic signs in controlled traffic scenarios but to vehicle sides and windows in uncontrolled encounters. Interactions were unlikely at controlled intersections, but various techniques were used to negotiate right-of-way in uncontrolled scenarios, e.g. cyclists used arm gestures and shoulder checks to communicate their intent and awareness when lane merging. Drivers communicated these through on-vehicle signals and head movements at roundabouts. We discuss the implications of driver-cyclist interaction behaviour on AV interaction design and offer insights into system requirements to support cyclists riding in traffic.