Exploring priority strategies at traffic signals for London's iBUS

The global positioning system (GPS) based automatic vehicle location (AVL) system recently procured by Transport for London (TfL) for bus fleet management, real time passenger information and bus priority at traffic signals is known as iBUS. In this system, buses are detected for priority purposes using detector locations configured in the on-bus computer and hence are also known as detectors. The predefined virtual detector coordinates are compared with the location of the bus obtained from the on-bus navigation system to trigger a priority request. This system eliminates the need of on-street hardware for detecting buses and provides much more flexibility in the number of detectors and their locations. This provides a real opportunity to implement more innovative bus priority methods.