Modeling Concepts for Mixed Traffic

Abstract

A first step is presented toward a simulation tool for shared space zones, including all three prevailing individual modes of transport: cars, bicycles, and walking. Unlike on conventional roads, the behavior in shared spaces cannot be modeled by following a predefined path and strictly obeying traffic rules because the architectural design allows for many more degrees of freedom. Therefore, the research focused on two main aspects: finding a path for each individual and handling potential conflicts with other individuals. A simulation tool is needed because many urban planners see shared space as a modern design concept for busy urban roads. A growing number of cities are interested in experimenting with shared space zones but are uncertain about safety issues and the effectiveness of the design. Although mature simulation tools exist for conventional road designs, no such tool is available for shared space designs because of the added degrees of freedom in movement and more-complex social interactions. To tackle these problems, an infrastructure model was created to help all agents find a path to their destinations. A separate system for handling conflict detects when two agents, following their individual paths, might collide. Game theory is used to resolve these conflicts by maximizing a utility function for different strategies. First results give a preliminary assessment of the functionality of the proposed simulation model for shared space zones and its calibration that uses real trajectories from an existing shared space.

Evaluation of Shared Space to Reduce Traffic Congestion

“…Some researchers have developed microsimulation models, based on social force theory, to model shared space [17][18][19]. Although the methodology used to create said models could be replicated and perhaps expanded to measure traffic parameters, it has been deemed to be too complex to be generalized.…”

“…In the model, this is determined by multiple metrics that are either measured or randomly assigned to drivers and pedestrians, such as which user arrived first, vehicle speed, distance away from the potential conflict, level of driver/pedestrian aggression, etc. These metrics are the same as those used in the social force approach models discussed earlier [17][18][19] and the variables that real-life shared space users would encounter in order to make a decision as either a pedestrian or driver. These factors make this approach the closest and most suitable for simulating shared space.…”

Modeling cyclist acceleration process for bicycle traffic simulation using naturalistic data

“…So the approach is usually computationally more expensive. Meanwhile, attempt has been made to represent the behavior of and interaction among cars, pedestrians and bicycles by a social force model (Schönauer et al, 2012). Logic models tend to include the detailed tactical behavior of cyclists.…”

Evaluation of Shared Space to Reduce Traffic Congestion: A case study on West Virginia University's Downtown Campus

“…Then, through conflict handling the game theory commences by creating a simple game between two players based off of a technique by Li and Chen, with the possibility of five choices. (Schonauer 2012) These choices are for the agent to remain on path, accelerate, decelerate, or swerve left or right, each with its own payoff value. This game is designed to be rational in a Stackelberg nonsymmetrical hierarchical fashion, with a leader and follower agent.…”

“…. (Schonauer 2012) In tests of this model, 60 pedestrian trajectories crossing a road were selected from video data, including 15 potential conflicts. The model was run through this data set with the underlying assumption that the pedestrian in this case would always be the leader.…”