A Bridge Deflection Measurement System Based On MCU

This paper use single-chip microcomputer and SCA100T chip for measuring deflection angle of bridge and calculating bridge deflection. One bridge deflection measurement system is studied in this paper for the measurement of long span bridge under the load of deflection with more accurately, safely and conveniently. The system is placed on the bridge, the measurement module firstly measures the deflection curve and two angles of vertical direction of the torsion curve, then transmits these data to the receiving device by Bluetooth. At the terminal, two angles subtraction to obtain the deflection angle and then through the input of the bridge length to calculate the deflection of the bridge. Among them, the angle measuring device is SCA100T-D01chip coming from Finland VTI company for its high accuracy dual axis tilt sensor; The central control unit is the8-bit AVR single chip Atmegal62coming from ATMEL company with high performance and low power; The wireless communication system using HC-05master-slave Bluetooth module; The terminal device is LJD-eWin4S equipped with advanced Windows CE embedded system. The paper launches from the following aspects concretely:The paper firstly introduces the background, the main research contents and the significance of the research. And it also analysis the principle of SCA100T, the single chip microcomputer Atmega162and the circuit principle of the main chip around the microcomputer.Then, the paper analysis the design idea of the deflection measurement system, which uses modular design method and is mainly divided into measurement module and terminal module. Among them, the measurement module’s core is the Atmega162single-chip microcomputer and it includes the central processing module, data transmission module, storage module data, measurement point module, power supply module and so on; The terminal module is LJD-eWin4S equipped with advanced Windows CE embedded system. Further more, the paper shows the function analysis and circuit design of each module.Based on the hardware platform, the paper designs the system flow, writes the source code to realize the software part, complete the module connection and the function realization. Among them, the measurement module through the ICCAVR software to compile the program, then debugs the code and generates a.HEX file, then write the.HEX file into microcomputer by the special AVR Studio software and the JTAG interface; while the terminal module uses Visual Studio2008to compile and debug the code, then completes the function of these modules.In conclusion, the software and hardware of the system were integrated to be tested with discovering and solving the problems. Through repeated testing and analysis of results shows that the deflection measurement system is running well and the measured results meet the requirements of the deflection measurement.