Some investigations of the freeway lane changing process

Abstract

This dissertation is concerned with the mathematical modeling of the delay and distance experienced by a vehicle making a lane change from one lane to the next adjacent lane using gap acceptance concepts. A lane change is assumed to be performed under either the full or partial process. The full process occurs when the attempting vehicle must wait for an acceptable gap after establishing a need for a lane change. The partial process occurs when the first encountered gap, after the need for a lane change has been established, is accepted. The partial process is further classified into two forms: form A, where an adjustment in the position of the attempting vehicle, relative to the accepted gap, is needed before the lane changing maneuver and form B, where the lane changing maneuver may be initiated immediately after the need for a lane change has been established. The full process is described by three phases. Phase 1 involves waiting for an acceptable gap. In Phase 2 the attempting vehicle is brought to such a position, relative to the accepted gap, so that the lane changing maneuver could be initiated and Phase 3 is the actual lane change maneuver. Form A of the partial process is composed of Phases 2 and 3 above. Form B, of the partial process, is composed of Phase 3 only. The delay and distance involved in each phase are described by appropriate probability distribution functions. These functions are derived partly from data collected in previous studies and partly through theoretical consideration. The gap acceptance policy of the driver is determined by an angular velocity model previously used in the analysis of the freeway merging problem..