Abstract :
In order to detect the bus overcrowding timely, design a system which is used M2M and signal processing in it. This system consists of a master node for remote wireless communication and two subordinate nodes for local communications in the vehicle, and that three nodes are star-connected. The tasks of the master node are to collect information from the subordinate nodes, and then to display and transfer it. The master node contains count display equipment, warning devices, and information transmission module. Set up two subordinate nodes for counting the numbers people inter the bus. The devices for counting include two units, signal acquisition unit is constituted with Pyroelectric infrared sensor which contains LHI778 probe and conditioning circuit, and the control unit is constituted with STC90C516 for signal processing. LCD screen is used to real-time display in each node for counting the person getting on and off the bus. If the number in the bus exceeds a set value, the system triggers an alarm device. When the alarm signal is not processed within the prescribed time, system will transfer the information of overcrowding vehicle to the control center using a wireless communication module. The manner of local communication is using Serial to WIFI.
