UC Berkeley

The tendency of buses to bunch is a problem that was defined almost 50 years ago. Since then, there has been a significant amount of work done on the problem; however, the tendency of the current literature is either to only focus on the surface causes or to rely on simulation to create results instead of model formulation. With GPS installed on many buses throughout the world, the data is only being used for monitoring and informing the user. This research proposes a new approach to solving the problem that uses the GPS data to directly counteract the cause of the bunching by allowing the buses to cooperate with each other and determine their speed based on relative position. A continuum approximation model is presented as a tool to systematically analyze the behavior of the system and test the proposed control. In order to validate the model and the control, a simulation tool is used to model the system in a more realistic, discrete way. The control is shown to produce bounded deviations in spacing consistent with those predicted by the model. The resulting bus system will not bunch with only a small reduction in commercial speed.