Freeway ramp merging phenomena in congested traffic using simulation combined with a driving simulator

Freeway ramp merging was studied under congested traffic conditions using a driving simulator (DS). First, the results of extensive macroscopic and microscopic studies were used to establish a model for the behavior of merging drivers. Based on this behavioral model, the Freeway Merging Capacity Simulation Program (FMCSP) was developed to simulate the actual traffic conditions. This model evaluates the capacity of a merging section for a given geometric design and flow condition. Next, a DS was developed to be used in conjunction with the FMCSP. The DS and simulation were combined by replacing one vehicle in the FMCSP by the DS. A pilot study was then undertaken to test for deficiencies in the combined system. Finally, the main DS experiment was performed using 12 male drivers. Driving behavior data were collected while each participant drove in the DS through the Ichinohashi merging section. In addition, two participants of the DS experiments drove an instrumented car through the real Ichinohashi merging section. The driving behavior data from the DS, instrumented car, and observation of drivers were compared to investigate the behavior of DS driver and examine differences between the behavior of drivers using simulators and those in the real world. The results indicated that the FMCSP is capable of simulating the actual traffic conditions of congested freeway ramp merging processes, and that the insertion into a simulation of a vehicle controlled by a DS is a promising tool for the study of complicated ramp merging phenomena.