Highlights • 69 in-depth vehicle-PTW accidents captured on video are analyzed. • A 5-steps human function failure model is used to excavate the accident causation. • Poor visibility exists widely in crossing and oncoming accident bundles. • A wider sensing area (field of view = 90°, view detection range = 35 m) is necessary to detect more effectively the conflict PTWs.

Abstract As the use of powered two-wheeler (PTW) becomes increasingly prevalent, PTW accidents are emerging as a major threat to the people’s life and property in China. Understanding the risky behaviors, psychological failures and kinematics in vehicle-to-PTW accidents is an important first step in addressing this issue. Here 69 vehicle-to-PTW accidents captured on video from the Traffic Accident Investigation and Research in China (TAIRC) database are selected and reconstructed. All accidents are categorized into different crash scenarios using a harmonized method. Accident causations are identified from the perspectives of praxeology and psychology. Kinematics characteristics, such as impact speed and relative position, are also analyzed. The results show the crossing accident bundle is the most frequent followed by rear, oncoming and run-up accident bundles, with proportions of 43.48 %, 27.54 %, 11.59 % and 17.39 % respectively. Accident causations of different crash scenarios have great differences whether in accident responsibilities or in psychological failures. For instance, the PTW riders who violate the traffic regulations need to be mainly responsible for most crossing accidents, whereas most rear accidents are blamed on drivers who fail to properly check their mirrors when they turn, turn around or change lanes. From the perspective of psychology, the perception failures encountered by both drivers and riders are a typical causation in crossing accidents, while it is a contributing factor in rear accidents that a failure of prognosis from the rider combined with a failure of perception from the driver. Visual obstruction exists widely in crossing and oncoming accident bundles. The impact speeds of vehicles and PTWs are often less than 40 km/h in all accident bundles. A wider sensing area (field of view = 90°, view detection range = 35 m) should be achieved to more effectively detect the conflict PTWs. These findings about vehicle-PTW accidents provide a stronger support for the development of prevention countermeasures and advanced driver assistance system.