Development of Auto Measuring System on Tred and Contact Pressure of Traffic Wheels

开发了一种能够自动连续监测交通流量和负荷的自动测量系统。其系统由以下三个子系统组成：(1)开关传感器垫：开关垫为800x7x7200mm柔性橡胶垫，开关传感器分为两组；主开关和触发开关。这种垫子放在覆盖车道的路面上，用胶带固定在路面上。车轮推动触发器和主开关。(2)数据记录箱：数据记录箱有ROM、RAM、定时器。72个主开关的开关位和车轮推动触发开关时的时间存储在RAM中。内存满后，RAM中的数据通过RS-232C或GPIB接口发送到额外的存储设备。(3)数据处理：附加存储器中的数据由微电脑处理。目前的软磨损可以在CRT或打印机上显示各种车型的交通量、行驶速度、车头时距、车辆中心和车轮横向位置的一些分布图。该系统可实现自动、长时间、简便的测量，且设备携带方便。

The auto measuring system which can automatically and continously moniters the traffic flows and loads has been developed. Its system consists of three subsystems as follows,(1) Switch senser mat : The switch mat is 800x7x7200mm flexible rubber mat. The switch sensors consists of two groupes;the main switch and the trigger switch. This mat is rested on the road covering the lanes and fixed to the road surface with cohiesive tape.Vehicle wheels push the trigger and main switchs.(2) Data logging box : Data logging box has its ROM and RAM ,timer. The on-off bits of 72 main switches and times when the wheels push the trigger switches store to RAM. After memory full,these data in RAM are sent to extra memory device with RS-232C or GPIB interface.(3) Data processing : Data in extra memory device are processed by microcomputer. The present soft-wears can display some distribution graphs of traffic volume of each vehicle type,moving speed,headway,spacing,center of vehicles and lateral position of wheels on CRT or printer.This system can be used to automatical,long-time,easy measurements and these equipmets are very portable.