Traffic Management

This report provides information on emerging technologies to improve the LOS of on-road public transport (ORPT), high-occupancy vehicles (HOVs) and emergency vehicles (EVs). A list of measures and technologies is compiled from this and earlier project reports. It includes the loop sensor which is suitable for detecting buses and trams at sites where they are separated spatially from other traffic. An emerging technology that can potentially replace an inductive loop is the Sensys Networks wireless sensor. In mixed traffic, a priority vehicle can be detected (identified) using a signposting or beacon together with an in-vehicle transponder. An emerging technology for implementing ORPT priority is the GPS. GPS technology is particularly suitable for implementing a top-down priority architecture, which is important for network or route-based priority. However, single-point GPS has an inherent position accuracy of 10 m and there is also a system delay of about 1 s. These constraints can be overcome to a large extent with differential GPS (using two units), location identification or odometer tracking to correct for position errors. Continuing research is being undertaken to make better use of the GPS technologies, and its application for active conditional priority is highly recommended. There is no single measure that can simply and adequately improve the LOS of ORPT, HOVs and EVs. For ORPT, a package of measures as described in this report will be necessary to increase its modal share. The usage and acceptance of HOV lanes can be assisted by emerging enforcement and tolling/smart card technologies. The LOS of EVs will continue to improve incrementally as the technologies for their detection and guidance mature.