Bus Bunching Control

On busy lanes, where public transport buses are frequent, bus bunching is a common phenomenon:

bunch1

Bunching leads to non-homogeneous utilization of buses and therefore degradation of service quality.

The objective is to (i) adhere buses to a timetable and (ii) guarantee equal headways.

The proposed control methodology is a shrinking horizon model predictive velocity control.

Different control strategies are considered:
(i)   timetable tracking: buses priorize the timetable over the headway reference.
(ii)   headway tracking: buses try to keep equal headways.
(iii)   balanced: both objectives are equally important.

The controllers are simulated in VISSIM in a realistic traffic setting (Göteborg):

bunch2

The system was evaluated in the event of severe perturbation

(Xdes: desired position, Xref: reference position, ETD: estimated time of departure):

bunch3

Related Publication:

Varga B, Tettamanti T and Kulcsár B (2018), "Optimally combined headway and timetable reliable public transport system", Transportation Research Part C: Emerging Technologies. Vol. 92, pp. 1 - 26.

https://doi.org/10.1016/j.trc.2018.04.016