Chaotic semi-express buses in a loop

Vee-Liem Saw; Luca Vismara; Lock Yue Chew

doi:10.1063/5.0039989

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arXiv · 2012.04865

Chaotic semi-express buses in a loop

Vee-Liem Saw·Luca Vismara·Lock Yue Chew

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Abstract

Urban mobility involves many interacting components: buses, cars, commuters, pedestrians, trains etc., making it a very complex system to study. Even a bus system responsible for delivering commuters from their origins to their destinations in a loop service already exhibits very complicated dynamics. Here, we investigate the dynamics of a simplified version of such a bus loop system consisting of two buses serving three bus stops. Specifically, we consider a configuration of one bus operating as a normal bus which picks up passengers from bus stops $A$ and $B$, and then delivers them to bus stop $C$, whilst the second bus acts as an express bus which picks up passengers only from bus stop $B$ and then delivers them to bus stop $C$. The two buses are like asymmetric agents coupled to bus stop $B$ as they interact via picking up passengers from this common bus stop. Intriguingly, this \emph{semi-express} bus configuration is more efficient and has a lower average waiting time for buses, compared to a configuration of two normal buses or a configuration of two express buses. We reckon the efficiency arises from the chaotic dynamics exhibited in the semi-express system, where the tendency towards anti-bunching is greater than that towards bunching, in contradistinction to the regular bunching behavior of two normal buses or the independent periodic behaviour of two non-interacting express buses.

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Vee-Liem Saw, Luca Vismara, Lock Yue Chew. 2020-12-09. Chaotic semi-express buses in a loop. https://doi.org/10.1063/5.0039989

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