Research And Implementation Of Data Acquisition System Based On Structural Health Monitoring

Data acquisition system of structural health monitoring is mainly used to automatic and scout measurement for rock and dust engineering and other engineering of water and electricity. It can predict disaster, become an assistant of making a policy, and save manpower by measuring big dams and others buildings pressure. This paper makes use of the vibrating wire and resistance strain sensor making health monitoring. They are widely used in all kings of aspects, such as water conservancy,water and electricity,railway,traffic,petroleum etc.The work principle and character of vibrating wire and resistance strain senor are elaborated in this paper. This dissertation carried on error analysis to sensors, emphasis on studies in the method and its realization electric circuit of reducing and eliminating sensors'error and increasing the precision.On the aspect of hardware circuit, it is made of seven parts:MCU,A/D,Oscillation,Signal adjustment,Communication,Channel select,Temperature adjustment. According to the request about data acquisition system of health monitoring sensor, P89C58X2FN will be as the main center processing unit, it will be charge multichannels data acquisition and data communication. About temperature adjustment, to measuring semiconductor resistor, a measuring method based on ratio for sampling and precision voltage to frequency converter is designed. In the position of not improving capability of component, it can improve the measurement precision much.With regard to the software design, software mainly complete MCU's initialization,interrupt acquisition and data communication. Besides, the main program uses the C language, which is advantageous for the readability and transportability. A new method which can be used to excite single coil vibrating wire sensor using technology of sweeping frequency is described. Compand with old methods, it has many advantages, for example, it's reliable to excite coil, easy to control the frequency of exciting and higher signal sensitivity.The system sample has been tested and operated for trial in the lab, the part of oscillation,data acquisition and communication have beem tested and validated. It makes an analysis about experiment data using Matlab software. The experiment indicates that the unit can work and satisfy the requirement of Data acquisition system of health monitoring sensor.