The roadside warning system COMPANION intend to warn drivers for incidents, disruptions in the traffic flow, adverse weather conditions etc by flashing light posts. As a basis for further work with this prototype system a series of experiments were conducted in order to measure the effects of system activation on individual drivers' behaviour and on traffic flow. The paper reports the identification of a collective safety process of "speed matching" following the activation of the warning system. Several methods of analysis, including Monte Carlo simulation techniques, support the conclusion that the proposed system will be effective in reducing secondary accidents. The warnings increases drivers' alertness and induce a more anticipating driving behaviour which in turn results in an increase in the "viscosity" of the traffic flow. This property reduces otherwise dangerous speed gradients. (A)
Samenvatting