Vehicles' type and engine power as factors affecting drivers' risk perception of the geometric characteristics of road network

The scope of this paper is to assess drivers' risk perception of the geometric characteristics bymonitoring-examining drivers' behaviour when driving on rural roads for a variety of car types having different engine power. The setup of the research was to monitor driving behaviour of 12 different drivers, driving 4 different vehicle types on 3 typical section of rural road network. The monitoring of driving behaviour was recorded using VBOX II and VideoVbox devices, which are Differential GPS based set of instruments, including a 3D accelerometer (Inertial Measuring Device). In order to assess driver's perception, the trial tests, were carried out trying to eliminateany kind of interference of other moving vehicles, humans or animals in order to avoid false data recording. The present paper presents the results of a research effort, which is dedicated to the detailed drivers' behaviour analysis. The first remarkable observations are:o The engine power of the vehicle leads to higher speed values for experienced drivers. The inexperienced drivers do not drive very fast in any case. All the drivers show aggressive behaviour when driving a sport car.o When driving vehicles with big engine power, the increasing rate of accelerationdecelerationis higher. This means that drivers' risk perception is reverse proportional to the safety feeling of driving powered cars.o For experienced drivers, the deceleration rate is much higher the acceleration rate. This can be explained by the fact that the experienced drivers are generally underestimating the risk, or overestimating their driving skills.A lot of research has to be done on drivers' behavioural analysis, in order to achieve betterroad alignment designs (beyond standard regulations and guidelines) and better signing, withemphasis to safety.