Vibrating-Wire-Sensors With Measuring Frequency System And Its Design Based On The Embedded μC/OS-Ⅱ System

Vibrating-Wire-Sensors with measuring frequency system is mainly used to auto- atic and scout measurement for the engineering of water and electricity and other rock and dust engineering. It can predict disaster, become an assistant of making a policy, and save manpower by measuring big dams and other buildings, displacement, pressure, strain, etc. A vibrating wire sensor is almost the only sensor burying in big dams and other buildings in rock and dust engineer and giving reliable data in a long time. It has a simple, solid and durable structure, a long period stability, and high precision and discre -tion. Its output is sign of frequency, it can directly interface with microcomputer by a long connection cable in order to transmit a long distance, especially, applying to a long distance measurement. As a result, it is widely used in all kings of aspects, such as water conservancy,water and electricity,railway,traffic,petroleum etc.This paper discusses a new method of measuring stress for large-scale structure by vibrating wire. The folowing contents are contained in this thesis:deriving the math em -atical model for the method of vibrating wire; formulating several ways of encouraging wire,producing the working principle and process;comparing the system with traditional model; improving the traditional method.At the same time, the paper combines the sys -tem with embedded operation system and describes, detailed ,the vibrating wiresensor, working principle,the exciting method and characteristic analysis. The technology of sweeping frequency and exciting vibrating wire is applied; And used The detection of vibrating wire faint sign is by applying filter and magnify technology; And usingμC/OS -Ⅱo peration system to attemper and manage the system software. Contemporari -ly, 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. In this syste -m, software for measuring vibrating wire frequency and other applying programs of this model are programmed in C language.From the theoretical and experimental analysises to the method for measuring stress in vibrating wire we can conclude,this method can not only meet the site and engineering demand completly in precision, but also be superior to the method of sticking strain slice of resistance and optical measurment in some fields,because it can be suitable to the spot more properly and can work for a longer time.