Headway and Platooning
Minimizing the headway and platooning are seen as solutions to increasing the capacity of transit systems. However, it is also possible to increase capacity by smarter scheduling, grouping passengers per destination. Platooning conversely also allows for decreasing the frequency while maintaining capacity. This ensures a lower intensity, ensuring grade separated intersections are required only for even higher capacities. The technologies allow for 2getthere’s GRT system to accommodate up to 8,500pphpd.
In the operational applications 2getthere has proven performance at a 5 second minimum headway, while actively developing towards 2 seconds. In terms of capacity the minimum headway should not be used to determine capacity as it can’t be guaranteed that there is a vehicle every slot. The average headway, which is determined by transit demand and the arrival pattern of passengers at stations, is leading. Once the average headway requirement becomes too low, especially for linear configurations, it makes sense to use larger vehicles.
With platooning, cooperative driving, multiple vehicles are linked virtually thus operting as a train. It allows to reduce the distance between vehicles even futher. 2getthere is applying the lessons learned from the European truck platooning challenge to reduce the distance between vehicles to 0.3 seconds. Currently 2getthere is contributing to the i-CAVE (integrated Cooperative Automated Vehicles) research program, with the focus on vehicles accelerating and braking simultaneously and being able to enter and leave the platoon on the fly.