One of the riskiest manoeuvres that a driver has to perform in a conventional highway system is to merge into the traffic and/or to perform a lane changing manoeuvre. Lane changing/merging collisions are responsible for one-tenth of all crash-caused traffic delays often resulting in congestion. Traffic delays and congestion, in general, increases travel time and has a negative economic impact. In this paper, we analyse the kinematics of the vehicles involved in a lane changing/merging manoeuvre, and study the conditions under which lane changing/merging crashes can be avoided. That is, given a particular lane change/merge scenario, we calculate the minimum longitudinal spacing which the vehicles involved should initially have so that no collision, of any type, takes place during the manoeuvre. Simulations of a number of examples of lane changing manoeuvres are used in order to demonstrate the results. These results together with appropriate sensors and equipment on board of vehicles could be used to assess the safety of lane changing manoeuvre and provide warnings or take evasive actions to avoid collision. (A)
Abstract