Modeling the lag of heading vehicle´s startup at intersections with mixed traffic

Because of the driver´s reaction time to the signal transformation and the vehicle´s response delay to the driver´s control action, there is always a delay time between the commence moment of the green interval and the startup of the heading vehicle in queue. This kind of delay time is defined as the start lag of heading vehicle (SLHV) in the research. The SLHV is an important fraction of the overall delay for a vehicle at the intersection. Under the mixed traffic condition, due to the frequent disturbances on motor vehicle by pedestrians and non-motor vehicles, the SLHV always increases dramatically and has much contribution to the overall delay of the heading vehicle at the intersection. Based on the video data of SLHV under mixed traffic situation in Beijing, this paper first adopted ANOVA to analyze possible effects that various factors act on the SLHV, finding that the lane function and the external disturbance have noticeable effect; nevertheless, the car type has less effect. And then it established a mathematical model to describe the SLHV. Finally it conducted a detailed study on the disturbing effect by pedestrians and non-motor vehicles. The results indicate that the SLHV increment caused by the disturbances is subject to a normal distribution. The work of this paper provides a new direction for improving estimation precision of vehicles delay at the intersection with mixed traffic.