New Microscopic Dynamic Model for Bicyclists’ Riding Strategies

Abstract

As more attention is focused on bicycles as a mode of transportation, there is a strong need to understand microscopic behaviors of bicyclists within urban traffic systems. To respond to these needs, a new approach to simulate bicyclists’ riding behaviors on bike paths has been developed. This approach uses the concept of reactive and perceptive ranges to depict the behaviors of bicycle flows. A series of riding strategies widely adopted by bike riders is proposed. Using these strategies or rules, this study applies a continuous psychological-physiological force (PPF) model to simulate the bicycle riding patterns and the reactive and perceptive interactions of bicyclists. A set of controlled experiments and field observations is carried out to calibrate the simulated interactions derived from the PPF model. After validation, the PPF model is used further to produce simulated trajectories of bicyclists, and a fundamental diagram is developed. The fundamental diagram is consistent with that in field investigations and previous research reports. A sensitivity analysis is also carried out based on the simulated trajectories of bicyclists (going through a series of bike paths with different widths). The analysis demonstrates that the width of a bike path directly impacts the capacity of the path. With the increasing width of a bike path, the capacity (per unit width of the bike path) decreases. This is a result of the psychological and physiological interactions of bicyclists in response to bike paths with different widths. This result provides a good insight for the design of bike paths in the future.