The impact of a passenger-safety-driven acceleration limit on the operation of a bus service

Document summary

Buses are a form of active transportation and can improve people’s well-being. However, their high level of acceleration can make them less attractive to users. Even worse, they can be responsible for severe injuries that require hospitalisation or for the development of fear of falling, particularly experienced by older people. Evidence has shown that, bus acceleration up to 1.0 m/s2 enables passengers to move in a natural way inside the moving vehicle, hence reducing instability and increasing safety. Although operators might be willing to implement such an intervention, they might also be skeptical about its impact on the operation of a service, such as timetabling, travel times, waiting times, etc. The effect of a safety-driven acceleration limit on the operational characteristics of a round trip of a bus service in London is investigated by this study. Data regarding speed, acceleration and journey time were extracted from the engine of a bus and recorded at 2 Hz. Further computations estimated the passenger waiting times and headways between the examined bus and its preceding and following buses. A vehicle movement model was used to test how these operational characteristics would be affected if the acceleration limit of 1.0 m/s2 were to be implemented. The results suggest that the journey time of the proposed accessible service would be 6 min longer than the current service and passenger waiting time would increase by 2 min. One additional bus would be required to serve the same number of passengers. A discussion of the results is provided.