Study On Bus Dispatching System And Development Of The Bus Onboard Information Terminal Unit

The public traffic system is main transportation means of modern central city, intelligent and information technique inevitably will be applied in transportation system in the future. Vehicle positioning technology is an important part of the public traffic information system. It provides the vehicle location information, which is disposed to meet firstly passenger needs and the bus dispatching center requirements secondly.Under the study of the vehicle positioning technology at home and abroad, a suit of system of bus-supervised system based on GIS is developed, which takes advantage of the technical progress in the fields such as electronic, computer, sensing and controlling. The system is composed of the bus monitor and schedule center, the public vehicle onboard information terminal unit and the electronic bus stop board.Based on the analysis types of positioning technology, the paper points out the characteristic of the bus positioning technology and focuses on types of positioning technology applied in bus. The bus doesn't need get more accurate its location by GPS. The positioning technology that applied in bus has great difference from others: for the bus driver is familiar with the current bus location, the bus needn't be navigated and positioned by GPS compared with other vehicles. The key problem is that let the monitor and schedule center and passenger know the bus current location. The bus runs in the changeless road. So even we know the bus' accurate location, we can only estimate the time that the bus arrives in station. Analyzed and compared with the GPS, the paper give birth to a new viewpoint----the bus positioning technology based on GIS. When the bus arrives in the station, the driver manipulates the terminal unit and sends the location information to the bus monitor and schedule center. Then the bus is shown its location in the electronic GIS map after the information is disposed. This paper is composed of the design of the public vehicle onboard information terminal unit and bus stop reporter's hardware circuit, the system's software and the wireless communication.The debugging results show the system basically completes the capability request, run stably, achieves the expectant goal.