PUBLIC TRANSPORTATION PRIORITY SYSTEM USING OPTICAL BUS DETECTORS

In Japan, along with an increase in traffic demand, traffic congestion has become constant, making it difficult for bus and other public mass transit systems to maintain their services on a scheduled time and fixed speed basis. To improve the situation, each prefectural police headquarters (HQ) has been studying public transportation priority systems (PTPS) for enhancing users' facilities by giving priority to public transportation with high transit efficiency. As part of the study, the Kumamoto Prefectural Police HQ developed and introduced a PTPS, which implements bus priority signal control and issues warnings to vehicles on exclusive bus lanes, using optical bus detectors. By using an optical distance-measurement method, these detectors measure the height of each vehicle running on the exclusive bus lane, discriminate between a bus and a vehicle, and output separate detection signals for buses and vehicles. By sending these signals to a signal control-related central processing unit or traffic control center, bus priority signal control can be effected and a rate of mixed vehicles on the exclusive bus lane can be processed statistically as well. To issue a warning to vehicles other than buses on the exclusive bus lane, a warning message is displayed on an information display board based on a warning signal output from the optical bus detector upon detection of the vehicle.