Dynamic Transit Priority Lanes in Urban Networks

Together with signal priority, dedication of space to public transport has been the most widely used policy to improve bus operations. Permanent dedicated bus lanes however can lead to an under-utilization of the available space. Dierent strategies such as intermittent bus lanes and bus lanes with intermittent priority try to make the priority lane usable for private vehicles during time windows where no bus is present. Dynamic control strategies focus on regulating the ow of cars on the priority lane, to achieve low-density mixed trac in which buses still have a time benet with respect to an all-mixed lane. A microsimulation framework is used to validate and extend the control strategy proposed by Anderson and Geroliminis (2020) [1] in a multi-modal urban network with xed passenger demand and modal split. A proportional linear feedback controller is applied to control the proportion of cars that can enter a dynamic priority lane using real-time trac metrics as input. The goal is to minimize the total passenger hours travelled (PHT) over all modes. For comparison, allowing static proportions of cars to use the priority lane has also been tested. At low congestion levels, dynamic control has been found to react as intended, but the total PHT did not improve with respect to the case with no priority lanes. The dynamic strategies have been found to perform better than their static counterparts. Other than a reduction in PHT, they also lead to a better spatial distribution of vehicles over the network.