Fig 1.
The microscopic model includes two layers, i.e., a tactical layer and an operational layer. The desired direction of movement is determined in the tactical layer. The operational layer determines the microscopic behavior when pedestrians interact with other agents.
Fig 2.
Desired exit position and desired direction.
The desired direction is assumed to be determined by the desired exit position of the crosswalk. The desired exit position is defined as the intersecting point of the curve of crosswalk edge and the desired walking trajectory.
Fig 3.
Truncated normal distribution.
The concept of truncated normal distribution is able to represent a distribution with arbitrary skewness and a specified range.
Fig 4.
Collision avoidance with counter-flow pedestrians.
(a) It is usually assumed that the magnitude of the repulsive force increases monotonically as the relative distance decreases. (b) It shows the case of valid and invalid conflicts.
Fig 5.
The relative time to collision (RTTC) is defined as the time difference between the first road user arriving at the potential conflicting location and the second road user arriving at this location if they keep their current speeds.
Fig 6.
The subject pedestrian will be attracted by the “footprints” of the pedestrians ahead with the same movement direction.
Fig 7.
There are two types of pedestrian giving-way maneuvers when the pedestrian-vehicle conflict occurs: waiting until the vehicle passes by and crossing before the vehicle passes by.
Fig 8.
The walking space is divided into separate cells where each cell is connected to each other by directed links.
Fig 9.
A vehicle is now represented by an ellipse with the radius which depends on the angle between the moving direction of the vehicle and the moving direction of a close-by pedestrian.
Fig 10.
Collection of trajectories for model calibration.
Empirical data were extracted using aerial videos captured by an optical camera with a 1920 × 1080 resolution mounted on a quadrotor with the flight altitude of about 40m-60m above the ground.
Table 1.
Parameter estimation for exit position.
Table 2.
Parameter estimation for desired speed.
Table 3.
Parameter estimation for “waiting/crossing” strategy.
Table 4.
Calibration results for social force model.
Fig 11.
(a) shows the pedestrian trajectories from real data and (b) shows simulation outputs.
Fig 12.
Simulation performance on speed, acceleration, direction change and crossing time.
(a) shows the average absolute error of walking speed. (b) shows the comparison of step-wise acceleration distributions. (c) shows the distribution of the step-wise direction change between current and previous directions. (d) shows the distribution of the crossing time at crosswalk.
Fig 13.
Fundamental diagrams of pedestrian flow.
The simulated fundamental diagrams are in good agreement with the observed ones.
Fig 14.
The evolution of the lane formation in one signal cycle.