Design & Realization Of Bridge Detection System Relay Module Based On The Short-range Wireless Communications Technology

Bridge detection can ensure the safe operation of bridge. But over the years, because of its inherent lag and inefficiency, the traditional methods of bridge detection which has high operating costs and the allocation of resources is unreasonable can not discover many bridge defects, burst signal, and respond to the emergencies. This situation can't meet modern bridges'requirements of real-time, efficient, emergency. The modern bridge equipments usually communicate with wires, but the detection can't be achieved under special circumstances or environment; at the same time, the detected nodes are too more, which makes the work of detection waste of time and effort, inefficiency, and the costs are high.After comparing the operating frequency, power, transmission rate and the number of network devices of several short-range wireless communication technologys, this design choose Wifi and Zigbee technology as the wireless solution. According to the requirements of bridge detection system, and combined with embedded technology, one bridge detection system relay based on the short-range wireless communications technology is introduced to realize data collection and forwarding. The relay is based on ARM9 hardware platform, embedded Linux software platform and Zigbee, Wifi technology. The project design and proof has been brought forward. In the hardware aspect, core board circuit, backplane circuit, as well as Zigbee, Wifi interface circuit have been designed and realized. The transplant of bootloader, filesystem, Linux core as well as the program of date acquisition and transmission have been realized in the software aspect. Finally, the design and implementation of the relay module was tested. The result tested in the lab indicates that this system may realize the 9600bit/s data collection and transmission, achieves the design requirements basically. Data collection and forwarding is realized wirelessly by the relay module. Inspector which receives data wirelessly from relay equals receiving data of all the nodes. The relay module greatly improves the efficiency and safety of the bridge detection, and save the costs.Been used in some place in which there are lots of data acquisition nodes and the communication can't be achieved with wires, the relay module has improved the efficiency, reduced the costs, enhanced reliability, and has a general sense to promote.