The minimum, maximum, mean, and majority values of the longitudinal distance, horizontal distance, and heading angle of the lane changing behavior will be obtained KSP inhibitors selleck using real field data. When the heading angle of a specific vehicle remains the same and the heading line changes, the driving activity is a lane changing activity. To describe the lane changing behavior, we select the origin point of XOY coordinate system as the start point of lane changing and make heading angle before lane
changing 0°, the minimum turning radius Rmin . If the lane changing behavior is a common type, the coordinate of terminal point (x, y) should meet y≥2Rmin, when x≥2Rmin,y≥2Rmin·sinarccos1−x2Rmin, when x<2Rmin. (1) We can indicate from (1) that the upper area in Figure 4 is the possible terminal point of a lane changing activity (without reverse). The dashed lines in Figure 4 are the corresponding trajectories. The larger
the minimum turning radius is, the more area common lane changing cannot achieve. Because the wheelbase is linear to the minimum turning radius, it would be more difficult for the vehicle with a long wheelbase to change its lane. Figure 4 Possible implement area of lane changing. 3.2. Lane Changing Activities Four actions will be taken by the drivers during the lane changing procedure: (1) turn the heading angle into an appropriate range by turning the steering wheel; (2) drive the vehicle to a suitable location of the target lane with the front wheel steering for 0°; (3) reverse the steering wheel to initialize the heading angle as step 1; (4) adjust the vehicle to its target trajectory. As shown in Figure 5, the corresponding vehicle movements can also be divided into four phases: twisting angle phase, approaching phase, closing angle phase, and adjustment phase. The lane changing behavior for an opponent side will be similar to the case shown in Figure 5 except for
the sign of the heading angle. In Figure 5, α is the heading angle of the vehicle body and β is the steering angle of the front wheel. Positive value means right turning. Figure 5 Vehicle movements during lane changing. 3.3. Calibration of the Lane Changing Behavior To obtain the longitudinal/horizontal displacements travelled during lane changing and other parameters utilized for the design of pre-signal system, we use real field AV-951 observed vehicle trajectory data to calibrate the selected parameters. As shown in Figure 6(a), we first applied a monitoring video of an extensive signalized intersections system (From Yantaxi Road-Chang’an Road intersection to Xiaozhai Road-Chang’an Road intersection) to explore vehicle interactions at the road section and intersection approach. The statistical results indicate that the vehicles at upstream will be at a free lane changing phase, which have little interaction with other vehicles.