In 2003, research funded by the UK Engineering and Physical Science Research Council and conducted by Dr. Ian Walker investigated human factors influencing the distance vehicle drivers gave when overtaking cyclists on roads. Using computer-aided detection equipment, the research showed several patterns of behaviour, each with various implications.
The study arose due to trends in UK cycling accidents suggesting that collisions in which vehicle drivers overtake cyclists result in a disproportionately high level of injury. A review of the experiences of 5000 cyclists reported that overtaking-related accidents accounted for less than 4% of the total accidents experienced. Such incidents however comprised almost 13% of officially recorded accidents, indicating an increased likelihood of police attention. These results also showed the increased level of danger arising from overtaking was coupled with consistency of age and gender in such collisions. To investigate these findings, an experiment was developed to research whether variables of appearance and riding style affect driver’s overtaking behaviour.
A standard pedal bike was refitted to include an ultrasonic distance sensor to measure the distance from the handlebar to an overtaking vehicle, a laptop running recording software, and a laser on the left-hand side of the handlebars to guide riding position on the road. To investigate the appearance of the cyclist, the use of a helmet was employed for some trials, and also the use of a long-haired wig was used to simulate the rider of the bike as female.
The results broke from a previously held belief among some veteran cyclists; that riding further into the centre of the road causes drivers giving more space when overtaking. Wearing a cycling helmet was also linked to reduced space when overtaking, and the appearance of a female cyclist resulted in more space given when overtaking. The results suggest more is needed to be done to promote safe driving when meeting various types of cyclists on the road.
For more information, please see:
Walker, I. (2007) Drivers overtaking bicyclists: Objective data on the effects of riding position, helmet use, vehicle type and apparent gender Accident Analysis and Prevention 39, 417-425
