The Design Of Highway Automatic Card Control System

After years of rapid development, the overall level of China’s highway has beengreatly improved, which has been promoting the development of China’stransportation industry. However, in recent years, with the continuous improvement ofpeople’s living standards, social vehicle ownership continues to increase, resulting inlarger highway traffic problems, especially at highway entrance. Highway automaticcard system can be a good solution to this problem, not only can reduce labor costs,but also can better solve the entrance congestion problem.For this project, the highway automatic card control system has a main controlsystem and two sets of upper and lower stations control systems, various systems basedon industrial STM32F103ZET6chip which based on ARM Cortex-M3as theprocessor, to ensure the system is good real-time and stability. The system has largetank capacity, the largest capacity can accommodate8000cards, and cards have wasterecycling capabilities, which greatly reduce the labor intensity. The advanced rub cardmode not only improves stability, but also can achieve the goal of card protection,reducing the failure rate of the card. The system adopts a modular design, the use ofCAN bus communication between the main card control system and internal controlsystem, to facilitate future maintenance and upgrading systems. The main controlsystem communicates via RS232and IPC, and through relays to write card controlantenna. The card control system use DC motors, stepper motors, photoelectricsensors, limit switches, touch force sensor, an electromagnet and a series of devices toachieve precise control of the card process, through the use of contact force sensors,the real-time monitoring system rub pressure card to improve the accuracy of thesystem rub card. Because the system working environment is bad, a series ofprotective measures was taken, moisture-proof and anti-overcurrent protection circuitboard is adopted, the usage of data protection and over-current protection DC motorAT25080EEPROM chip on the system after power down, all greatly improves thestability and reliability of the system.This article attempts to elaborate on the significance of the research, the researchstatus, each module system hardware design and software design and other aspects.Firstly, introducing the purpose of the research and the status of current research athome and abroad, on this basis, we raise of the proposed system performance, compared with similar products’ advantage. According to the proposed performanceindicators, it raises the design project systematically, and lists examples ofcommunication protocol agreements, then introduces the hardware circuit design ofeach module of the system and software design ideas. Finally it describes the processof hardware and software parts debugging systematically, analyzing the problems andsolutions during process of debugging, and record the debugging data. After severaltests on site, hysteresis card rate of the system is less than1/20000, issuing time is lessthan3s, meeting the design requirements, and it is recently put on the market.